[opensuse] Use entire disk, and not a partition
If you have a disk, let's say /dev/sda, and instead of creating partitions on the disk, for example /dev/sda1, you use the entire disk, format it, and allocate it to an application - will this cause any problems ? In short: the application points to and uses /dev/sda (which is mounted), instead of /dev/sda1. Dirk *** Disclaimer *** The information contained in this e-mail is confidential and legally privileged and is intended solely for the addressee and to others who have the authority to receive it. Access to this e-mail by anyone else is unauthorized and as such, any disclosure, copying, distribution or any action taken or omitted in reliance on it is unlawful. If you have received this e-mail in error, please notify the sender immediately. The views expressed in this e-mail are the views of the individual sender and should in no way be construed as the views of the Company. The Company is not liable to ensure that outgoing e-mails are virus-free. The Company is not liable, should information or data, for whatever reason, be corrupted or fail to reach its intended addressee. The Company is not liable for any loss or damage of whatsoever nature and howsoever arising resulting from the opening or the use of the information in this e-mail, including its attachments and links. The sender of this e-mail is subject to and bound by the terms and conditions of Company+IBk-s Electronic Communications Usage Policy. -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org
On Wed, 13 Feb 2008, Dirk Moolman wrote:-
If you have a disk, let's say /dev/sda, and instead of creating partitions on the disk, for example /dev/sda1, you use the entire disk, format it, and allocate it to an application - will this cause any problems ?
What do you mean by "allocate it to an application" ? Do you mean something like creating a file system on the device, mounting it on /srv/www and leaving it just for Apache2? If so, it shouldn't. If not, how about giving a concrete example of what you mean?
In short: the application points to and uses /dev/sda (which is mounted), instead of /dev/sda1.
Unless the application is specifically manipulating devices, it's not going to be using /dev/sda but will use whatever directory /dev/sda uses as the mount point. Regards, David Bolt -- Team Acorn: http://www.distributed.net/ OGR-P2 @ ~100Mnodes RC5-72 @ ~15Mkeys SUSE 10.1 32bit | openSUSE 10.2 32bit | openSUSE 10.3 32bit | openSUSE 11.0a1 SUSE 10.1 64bit | openSUSE 10.2 64bit | openSUSE 10.3 64bit RISC OS 3.6 | TOS 4.02 | openSUSE 10.3 PPC | RISC OS 3.11 -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org
Sorry, let me explain. We are using Oracle. Oracle uses filesystems to create datafiles in, for example it will create files like: /oradata01/system01.dbf /oradata02/users01.dbf Now if /oradata02 (a new filesystem I created) points to the device /dev/sda, instead of /dev/sda1 (a partition on sda), will this be a problem ? It formatted and mounted fine, without any problems, and Oracle is ok with the space. I just don't want to run into problems further down the line, so I just want to make sure it is ok like this. With some Unix systems you have to be careful with your device partitions, and your offsets that you use, but I don't have much experience on Linux, and just want to confirm that the above setup will be ok. Dirk -----Original Message----- From: David Bolt [mailto:bcrafhfr@davjam.org] Sent: 13 February 2008 01:03 PM To: opensuse@opensuse.org Subject: Re: [opensuse] Use entire disk, and not a partition On Wed, 13 Feb 2008, Dirk Moolman wrote:-
If you have a disk, let's say /dev/sda, and instead of creating partitions on the disk, for example /dev/sda1, you use the entire disk, format it, and allocate it to an application - will this cause any problems ?
What do you mean by "allocate it to an application" ? Do you mean something like creating a file system on the device, mounting it on /srv/www and leaving it just for Apache2? If so, it shouldn't. If not, how about giving a concrete example of what you mean?
In short: the application points to and uses /dev/sda (which is mounted), instead of /dev/sda1.
Unless the application is specifically manipulating devices, it's not going to be using /dev/sda but will use whatever directory /dev/sda uses as the mount point. Regards, David Bolt -- Team Acorn: http://www.distributed.net/ OGR-P2 @ +AH4-100Mnodes RC5-72 @ +AH4-15Mkeys SUSE 10.1 32bit | openSUSE 10.2 32bit | openSUSE 10.3 32bit | openSUSE 11.0a1 SUSE 10.1 64bit | openSUSE 10.2 64bit | openSUSE 10.3 64bit RISC OS 3.6 | TOS 4.02 | openSUSE 10.3 PPC | RISC OS 3.11 -- To unsubscribe, e-mail: opensuse+-unsubscribe@opensuse.org For additional commands, e-mail: opensuse+-help@opensuse.org *** Disclaimer *** The information contained in this e-mail is confidential and legally privileged and is intended solely for the addressee and to others who have the authority to receive it. Access to this e-mail by anyone else is unauthorized and as such, any disclosure, copying, distribution or any action taken or omitted in reliance on it is unlawful. If you have received this e-mail in error, please notify the sender immediately. The views expressed in this e-mail are the views of the individual sender and should in no way be construed as the views of the Company. The Company is not liable to ensure that outgoing e-mails are virus-free. The Company is not liable, should information or data, for whatever reason, be corrupted or fail to reach its intended addressee. The Company is not liable for any loss or damage of whatsoever nature and howsoever arising resulting from the opening or the use of the information in this e-mail, including its attachments and links. The sender of this e-mail is subject to and bound by the terms and conditions of Company+IBk-s Electronic Communications Usage Policy. -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 The Wednesday 2008-02-13 at 13:51 +0200, Dirk Moolman wrote:
Sorry, let me explain.
We are using Oracle. Oracle uses filesystems to create datafiles in, for example it will create files like:
/oradata01/system01.dbf /oradata02/users01.dbf
Now if /oradata02 (a new filesystem I created) points to the device /dev/sda, instead of /dev/sda1 (a partition on sda), will this be a problem ?
As far as I know, which isn't that much, there should be no problem. I assume the space is initialized (mkfs)? You can test it: write a file using the entire space in the disk (dd if=/dev/null of=...), check the kernel log. It is also possible to write a single file to a device, without filesystem (raw). I understand some databases did/do that. Being a entire device there is no problem with partition limits and overwriting another partition space, and it is supposed to be faster. - -- Cheers, Carlos E. R. -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.4-svn0 (GNU/Linux) iD8DBQFHsujmtTMYHG2NR9URAiDeAJ9JuIX3q2yrCzmYYR2BJJ8NPCQmAACfVxpG 38dlv9YacJQU9ee2If8AhOI= =ZnAw -----END PGP SIGNATURE----- -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org
Carlos E. R. wrote:
The Wednesday 2008-02-13 at 13:51 +0200, Dirk Moolman wrote:
Sorry, let me explain.
We are using Oracle. Oracle uses filesystems to create datafiles in, for example it will create files like:
/oradata01/system01.dbf /oradata02/users01.dbf
Now if /oradata02 (a new filesystem I created) points to the device /dev/sda, instead of /dev/sda1 (a partition on sda), will this be a problem ?
I don't believe you can do this. I may be wrong but I believe you will need to create a single partition /dev/sda1 that encompasses the entire disk and use that.
As far as I know, which isn't that much, there should be no problem. I assume the space is initialized (mkfs)? You can test it: write a file using the entire space in the disk (dd if=/dev/null of=...), check the kernel log.
It is also possible to write a single file to a device, without filesystem (raw). I understand some databases did/do that. Being a entire device there is no problem with partition limits and overwriting another partition space, and it is supposed to be faster.
As for raw devices, I believe you can use the raw command to bind a raw device to a disk partition. The speed improvement is not due to the partition structure but the raw construct. The database engine is free to handle the I/O with the device rather than having to deal with the inefficiencies/help of the filesystem.
-- Cheers, Carlos E. R.
-- kr -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org
-----Original Message----- *** Disclaimer *** The information contained in this e-mail is confidential and legally privileged and is intended solely for the addressee and to others who have the authority to receive it. Access to this e-mail by anyone else is unauthorized and as such, any disclosure, copying, distribution or any action taken or omitted in reliance on it is unlawful. If you have received this e-mail in error, please notify the sender immediately. The views expressed in this e-mail are the views of the individual sender and should in no way be construed as the views of the Company. The Company is not liable to ensure that outgoing e-mails are virus-free. The Company is not liable, should information or data, for whatever reason, be corrupted or fail to reach its intended addressee. The Company is not liable for any loss or damage of whatsoever nature and howsoever arising resulting from the opening or the use of the information in this e-mail, including its attachments and links. The sender of this e-mail is subject to and bound by the terms and conditions of Company+IBk-s Electronic Communications Usage Policy. From: K.R. Foley [mailto:kr@cybsft.com]=20 Sent: 13 February 2008 04:05 PM To: Carlos E. R. Cc: OS-en Subject: Re: [opensuse] Use entire disk, and not a partition
Carlos E. R. wrote:
=20 =20 The Wednesday 2008-02-13 at 13:51 +0200, Dirk Moolman wrote: =20 =20
Sorry, let me explain. =20 We are using Oracle. Oracle uses filesystems to create datafiles in, for example it will create files like: =20 /oradata01/system01.dbf /oradata02/users01.dbf =20 =20 Now if /oradata02 (a new filesystem I created) points to the device /dev/sda, instead of /dev/sda1 (a partition on sda), will this be a problem ?
I don't believe you can do this. I may be wrong but I believe you will need to create a single partition /dev/sda1 that encompasses the entire disk and use that.
The thing is, I already did. I was able to format the entire disk (/dev/sda) using a tool Oracle provides, without creating a partition on the disk (so I skipped the fdisk part), and then did a mkfs (using mkfs.ocfs - also provided by Oracle), and then I mounted the device (/dev/sda). This worked fine, and I can write to the new filesystem (/oradata02) /etc/fstab ----------- /dev/sda /oradata02 ocfs defaults 0 0 Dirk -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org
Dirk Moolman wrote:
-----Original Message-----
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From: K.R. Foley [mailto:kr+AEA-cybsft.com]=20 Sent: 13 February 2008 04:05 PM To: Carlos E. R. Cc: OS-en Subject: Re: [opensuse] Use entire disk, and not a partition
Carlos E. R. wrote:
=20 =20 The Wednesday 2008-02-13 at 13:51 +020-, Dirk Moolman wrote: =20 =20
Sorry, let me explain. =20 We are using Oracle. Oracle uses filesystems to create datafiles in, for example it will create files like: =20 /oradata01/system01.dbf /oradata02/users01.dbf =20 =20 Now if /oradata02 (a new filesystem I created) points to the device /dev/sda, instead of /dev/sda1 (a partition on sda), will this be a problem ?
I don't believe you can do this. I may be wrong but I believe you will need to create a single partition /dev/sda1 that encompasses the entire disk and use that.
The thing is, I already did. I was able to format the entire disk (/dev/sda) using a tool Oracle provides, without creating a partition on the disk (so I skipped the fdisk part), and then did a mkfs (using mkfs.ocfs - also provided by Oracle), and then I mounted the device (/dev/sda). This worked fine, and I can write to the new filesystem (/oradata02)
/etc/fstab ----------- /dev/sda /oradata02 ocfs defaults 0 0
Dirk
I stand corrected. Multiple times from the look of the other emails. :) -- kr -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org
Dirk Moolman wrote:
-----Original Message-----
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The information contained in this e-mail is confidential and legally privileged and is intended solely for the addressee and to others who have the authority to receive it. Access to this e-mail by anyone else is unauthorized and as such, any disclosure, copying, distribution or any action taken or omitted in reliance on it is unlawful. If you have received this e-mail in error, please notify the sender immediately.
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From: K.R. Foley [mailto:kr+AEA-cybsft.com]=20 Sent: 13 February 2008 04:05 PM To: Carlos E. R. Cc: OS-en Subject: Re: [opensuse] Use entire disk, and not a partition
Carlos E. R. wrote:
=20 =20 The Wednesday 2008-02-13 at 13:51 +020-, Dirk Moolman wrote: =20 =20
Sorry, let me explain. =20 We are using Oracle. Oracle uses filesystems to create datafiles in, for example it will create files like: =20 /oradata01/system01.dbf /oradata02/users01.dbf =20 =20 Now if /oradata02 (a new filesystem I created) points to the device /dev/sda, instead of /dev/sda1 (a partition on sda), will this be a problem ?
I don't believe you can do this. I may be wrong but I believe you will need to create a single partition /dev/sda1 that encompasses the entire disk and use that.
The thing is, I already did. I was able to format the entire disk (/dev/sda) using a tool Oracle provides, without creating a partition on the disk (so I skipped the fdisk part), and then did a mkfs (using mkfs.ocfs - also provided by Oracle), and then I mounted the device (/dev/sda). This worked fine, and I can write to the new filesystem (/oradata02)
It will "work fine" right up until the disk is moved to another system, and a new systems admin doesn't know that this disk doesn't have a partition table, and while attempting to pull data off, comes to the logical conclusion that the partition table needs to be repaired before he can proceed -- at which point, he's now overwriting the start of your oracle data. Do things properly, and use the damned partition table. I can't believe that the 1 or 2 disk blocks reserved for the partition table are going to be the difference between your Oracle database having enough storage space or not.
/etc/fstab ----------- /dev/sda /oradata02 ocfs defaults 0 0
When a newbie sysadmin, for whatever reason (say during the course of some trouble-shooting) does this: +ACM- fdisk /dev/sda and when he sees nonsense in what fdisk thinks is a partition table, he attempts to correct it by specifying sda1 to cover the whole disk, and all the rest being empty, what will happen? -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 The Wednesday 2008-02-13 at 08:04 -0600, K.R. Foley wrote:
Now if /oradata02 (a new filesystem I created) points to the device /dev/sda, instead of /dev/sda1 (a partition on sda), will this be a problem ?
I don't believe you can do this. I may be wrong but I believe you will need to create a single partition /dev/sda1 that encompasses the entire disk and use that.
It is simple enough to test, but I don't have a spare disk to do the testing right now. I have seen that kind of use before, if my memory doesn't fail me.
It is also possible to write a single file to a device, without filesystem (raw). I understand some databases did/do that. Being a entire device there is no problem with partition limits and overwriting another partition space, and it is supposed to be faster.
As for raw devices, I believe you can use the raw command to bind a raw device to a disk partition. The speed improvement is not due to the partition structure but the raw construct.
I didn't mean that it was for the partition structure, but for the filesystem. - -- Cheers, Carlos E. R. -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.4-svn0 (GNU/Linux) iD8DBQFHswbitTMYHG2NR9URAg0OAJ0S4HTGPfYMp4Wqdo3FuzFEmgmgXACgk6n6 v4aTQHFiu1hzhh/2TrKEgSo= =uTCm -----END PGP SIGNATURE----- -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org
On Wed, 13 Feb 2008, Carlos E. R. wrote:-
The Wednesday 2008-02-13 at 08:04 -0600, K.R. Foley wrote:
Now if /oradata02 (a new filesystem I created) points to the device /dev/sda, instead of /dev/sda1 (a partition on sda), will this be a problem ?
I don't believe you can do this. I may be wrong but I believe you will need to create a single partition /dev/sda1 that encompasses the entire disk and use that.
It is simple enough to test, but I don't have a spare disk to do the testing right now.
Virtual machines are so useful at times :-) Here's one test using a 2GB virtual drive. It's using /dev/sdb as the device because /dev/sda contains the OS and I don't quite feel like wiping that yet: lifter:~ # fdisk -l /dev/sdb Disk /dev/sdb: 2147 MB, 2147483648 bytes 255 heads, 63 sectors/track, 261 cylinders Units = cylinders of 16065 * 512 = 8225280 bytes Disk identifier: 0x00000000 Disk /dev/sdb doesn't contain a valid partition table lifter:~ # mkxfs /dev/sdb -bash: mkxfs: command not found lifter:~ # mke2fs /dev/sdb mke2fs 1.40.2 (12-Jul-2007) /dev/sdb is entire device, not just one partition! Proceed anyway? (y,n) y Filesystem label= OS type: Linux Block size=4096 (log=2) Fragment size=4096 (log=2) 262144 inodes, 524288 blocks 26214 blocks (5.00%) reserved for the super user First data block=0 Maximum filesystem blocks=536870912 16 block groups 32768 blocks per group, 32768 fragments per group 16384 inodes per group Superblock backups stored on blocks: 32768, 98304, 163840, 229376, 294912 Writing inode tables: done Writing superblocks and filesystem accounting information: done This filesystem will be automatically checked every 38 mounts or 180 days, whichever comes first. Use tune2fs -c or -i to override. lifter:~ # mount /dev/sdb /mnt lifter:~ # ls /mnt lost+found lifter:~ # umount /mnt lifter:~ # mkreiserfs /dev/sdb mkreiserfs 3.6.20 Copyright (C) 2001-2005 by Hans Reiser, licensing governed by reiserfsprogs/COPYING. A pair of credits: Hans Reiser was the project initiator, source of all funding for the first 5.5 years. He is the architect and official maintainer. Edward Shushkin wrote the encryption and compression file plugins, and the V3 journal relocation code. /dev/sdb is entire device, not just one partition! Use -f to force over lifter:~ # mkreiserfs /dev/sdb -f mkreiserfs 3.6.20 Copyright (C) 2001-2005 by Hans Reiser, licensing governed by reiserfsprogs/COPYING. A pair of credits: Many persons came to www.namesys.com/support.html, and got a question answered for $25, or just gave us a small donation there. Hans Reiser was the project initiator, source of all funding for the first 5.5 years. He is the architect and official maintainer. /dev/sdb is entire device, not just one partition! Continue (y/n):y Guessing about desired format.. Kernel 2.6.24-rc7-git5-2-pae is running. Format 3.6 with standard journal Count of blocks on the device: 524288 Number of blocks consumed by mkreiserfs formatting process: 8227 Blocksize: 4096 Hash function used to sort names: "r5" Journal Size 8193 blocks (first block 18) Journal Max transaction length 1024 inode generation number: 0 UUID: 74a4a6b0-13f3-4c66-b536-a0e75f467163 Syncing..ok ReiserFS is successfully created on /dev/sdb. lifter:~ # mount /dev/sdb /mnt lifter:~ # ls -l /mnt total 0 lifter:~ # umount /mnt lifter:~ # fdisk -l /dev/sdb Disk /dev/sdb: 2147 MB, 2147483648 bytes 255 heads, 63 sectors/track, 261 cylinders Units = cylinders of 16065 * 512 = 8225280 bytes Disk identifier: 0x00000000 Disk /dev/sdb doesn't contain a valid partition table lifter:~ # Regards, David Bolt -- Team Acorn: http://www.distributed.net/ OGR-P2 @ ~100Mnodes RC5-72 @ ~15Mkeys SUSE 10.1 32bit | openSUSE 10.2 32bit | openSUSE 10.3 32bit | openSUSE 11.0a1 SUSE 10.1 64bit | openSUSE 10.2 64bit | openSUSE 10.3 64bit RISC OS 3.6 | TOS 4.02 | openSUSE 10.3 PPC | RISC OS 3.11 -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 The Wednesday 2008-02-13 at 15:43 -0000, David Bolt wrote:
It is simple enough to test, but I don't have a spare disk to do the testing right now.
Virtual machines are so useful at times :-)
Ah! How right you are! I forgot. ... Point proven, I see. - -- Cheers, Carlos E. R. -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.4-svn0 (GNU/Linux) iD8DBQFHszj0tTMYHG2NR9URAux1AKCOx05xP57KSdtFeIWEwDnhhwUWmQCfQbtn WxrFb8p35wBA+OCmucQ9hUA= =HIcq -----END PGP SIGNATURE----- -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org
Carlos E. R. pecked at the keyboard and wrote:
partition structure but the raw construct.
I didn't mean that it was for the partition structure, but for the filesystem.
Oracle has been doing this for years (over 10 that I know of), using the raw disk to store data. No need to create a filesystem at all. -- Ken Schneider SuSe since Version 5.2, June 1998 -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org
-----Original Message----- From: Ken Schneider [mailto:suse-list3@bout-tyme.net] Sent: 13 February 2008 06:10 PM To: opensuse@opensuse.org Subject: Re: [opensuse] Use entire disk, and not a partition
Carlos E. R. pecked at the keyboard and wrote:
partition structure but the raw construct.
I didn't mean that it was for the partition structure, but for the filesystem.
Oracle has been doing this for years (over 10 that I know of), using the raw disk to store data. No need to create a filesystem at all.
This is the way I used to do it with Informix - using raw devices. We migrated to Oracle, and I had to learn Oracle from scratch. My (new) collegues, who worked on Oracle for years, says raw device is not necessary, which I found strange. They say Oracle is fast enough on cooked files. :-o Oh well, I'm not the senior dba anymore, so I just go with their recommendations. Dirk *** Disclaimer *** The information contained in this e-mail is confidential and legally privileged and is intended solely for the addressee and to others who have the authority to receive it. Access to this e-mail by anyone else is unauthorized and as such, any disclosure, copying, distribution or any action taken or omitted in reliance on it is unlawful. If you have received this e-mail in error, please notify the sender immediately. The views expressed in this e-mail are the views of the individual sender and should in no way be construed as the views of the Company. The Company is not liable to ensure that outgoing e-mails are virus-free. The Company is not liable, should information or data, for whatever reason, be corrupted or fail to reach its intended addressee. The Company is not liable for any loss or damage of whatsoever nature and howsoever arising resulting from the opening or the use of the information in this e-mail, including its attachments and links. The sender of this e-mail is subject to and bound by the terms and conditions of Company+IBk-s Electronic Communications Usage Policy. -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org
Dirk Moolman pecked at the keyboard and wrote:
-----Original Message----- From: Ken Schneider [mailto:suse-list3@bout-tyme.net] Sent: 13 February 2008 06:10 PM To: opensuse@opensuse.org Subject: Re: [opensuse] Use entire disk, and not a partition
Carlos E. R. pecked at the keyboard and wrote:
partition structure but the raw construct. I didn't mean that it was for the partition structure, but for the filesystem.
Oracle has been doing this for years (over 10 that I know of), using the raw disk to store data. No need to create a filesystem at all.
This is the way I used to do it with Informix - using raw devices. We migrated to Oracle, and I had to learn Oracle from scratch. My (new) collegues, who worked on Oracle for years, says raw device is not necessary, which I found strange. They say Oracle is fast enough on cooked files.
:-o Oh well, I'm not the senior dba anymore, so I just go with their recommendations.
Ah yes, Informix indeed. I looked back through some of the backup programs I wrote to backup the DB and it stated Oracle but I think that was earlier. The company claimed then it was much faster to write to the raw disk. With disks being much faster today that probably is not as true. Yep, when you are not in charge you need to go with the flow. -- Ken Schneider SuSe since Version 5.2, June 1998 -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org
Ken Schneider wrote:
Dirk Moolman pecked at the keyboard and wrote:
-----Original Message----- From: Ken Schneider [mailto:suse-list3@bout-tyme.net] Sent: 13 February 2008 06:10 PM To: opensuse@opensuse.org Subject: Re: [opensuse] Use entire disk, and not a partition
Carlos E. R. pecked at the keyboard and wrote:
partition structure but the raw construct. I didn't mean that it was for the partition structure, but for the filesystem.
Oracle has been doing this for years (over 10 that I know of), using the raw disk to store data. No need to create a filesystem at all.
This is the way I used to do it with Informix - using raw devices. We migrated to Oracle, and I had to learn Oracle from scratch. My (new) collegues, who worked on Oracle for years, says raw device is not necessary, which I found strange. They say Oracle is fast enough on cooked files.
:-o Oh well, I'm not the senior dba anymore, so I just go with their recommendations.
Ah yes, Informix indeed. I looked back through some of the backup programs I wrote to backup the DB and it stated Oracle but I think that was earlier. The company claimed then it was much faster to write to the raw disk. With disks being much faster today that probably is not as true. Yep, when you are not in charge you need to go with the flow.
Using a filesystem is always an extra overhead compared using the Oracle or Informix use of a raw partition, because all disk access going through TWO levels of storage/access libraries rather than just one. Faster disk drives actually INCREASES the negative impact of not using raw devices (because that means that the CPU-side delay from filesystem overhead is now a greater impact on read/write delays). -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org
On Wed, 13 Feb 2008, K.R. Foley wrote:-
I don't believe you can do this. I may be wrong but I believe you will need to create a single partition /dev/sda1 that encompasses the entire disk and use that.
No, no need for any partitions: From man reiserfs: DESCRIPTION mkreiserfs creates a Linux ReiserFS filesystem on a device (usually a disk parâ tition). device is the special file corresponding to a device or to a partition (e.g /dev/hdXX for an IDE disk partition or /dev/sdXX for a SCSI disk partiâ tion). And man mke2fs: DESCRIPTION mke2fs is used to create an ext2/ext3 filesystem (usually in a disk partition). device is the special file corresponding to the device (e.g /dev/hdXX). blocks- count is the number of blocks on the device. If omitted, mke2fs automagically figures the file system size. If called as mkfs.ext3 a journal is created as if the -j option was specified. Man mkfs.xfs: DESCRIPTION mkfs.xfs constructs an XFS filesystem by writing on a special file using the values found in the arguments of the command line. It is invoked automatically by mkfs(8) when it is given the -t xfs option. In its simplest (and most commonly used form), the size of the filesystem is determined from the disk driver. As an example, to make a filesystem with an internal log on the first partition on the first SCSI disk, use: mkfs.xfs /dev/sda1 Usually, they're used to create a file system on a partition, but they can be used to build the file system on the block device and it is then able to be mounted using the plain device, e.g. /dev/sda Regards, David Bolt -- Team Acorn: http://www.distributed.net/ OGR-P2 @ ~100Mnodes RC5-72 @ ~15Mkeys SUSE 10.1 32bit | openSUSE 10.2 32bit | openSUSE 10.3 32bit | openSUSE 11.0a1 SUSE 10.1 64bit | openSUSE 10.2 64bit | openSUSE 10.3 64bit RISC OS 3.6 | TOS 4.02 | openSUSE 10.3 PPC | RISC OS 3.11 -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org
K.R. Foley wrote:
Carlos E. R. wrote:
The Wednesday 2008-02-13 at 13:51 +0200, Dirk Moolman wrote:
Sorry, let me explain. We are using Oracle. Oracle uses filesystems to create datafiles in, for example it will create files like: /oradata01/system01.dbf /oradata02/users01.dbf
Now if /oradata02 (a new filesystem I created) points to the device /dev/sda, instead of /dev/sda1 (a partition on sda), will this be a problem ?
I don't believe you can do this. I may be wrong but I believe you will need to create a single partition /dev/sda1 that encompasses the entire disk and use that.
As far as I know, which isn't that much, there should be no problem. I assume the space is initialized (mkfs)? You can test it: write a file using the entire space in the disk (dd if=/dev/null of=...), check the kernel log.
It is also possible to write a single file to a device, without filesystem (raw). I understand some databases did/do that. Being a entire device there is no problem with partition limits and overwriting another partition space, and it is supposed to be faster.
As for raw devices, I believe you can use the raw command to bind a raw device to a disk partition. The speed improvement is not due to the partition structure but the raw construct. The database engine is free to handle the I/O with the device rather than having to deal with the inefficiencies/help of the filesystem.
Oracle expects a raw block device (such as a disk drive), not a raw character device, so there is no need to use the raw command -- that will just slow things down -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org
On Wed, 13 Feb 2008 08:04:35 -0600, K.R. Foley wrote:
I don't believe you can do this.
You can. That way you use a disk as a superfloppy, i.e. you don't create a partition table. If you couldn't do that, you also couldn't use dd to read or write from/to an entire disk. Philipp -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org
On Wed, 13 Feb 2008, Carlos E. R. wrote:-
The Wednesday 2008-02-13 at 13:51 +0200, Dirk Moolman wrote:
Sorry, let me explain.
We are using Oracle. Oracle uses filesystems to create datafiles in, for example it will create files like:
/oradata01/system01.dbf /oradata02/users01.dbf
Now if /oradata02 (a new filesystem I created) points to the device /dev/sda, instead of /dev/sda1 (a partition on sda), will this be a problem ?
As far as I know, which isn't that much, there should be no problem.
There isn't. Reiserfs, ext2/3 and XFS all support file systems that use the entire device, not just a partition. While I haven't tried it, JFS may also support it as well.
It is also possible to write a single file to a device, without filesystem (raw). I understand some databases did/do that. Being a entire device there is no problem with partition limits and overwriting another partition space, and it is supposed to be faster.
Well, it's not going to have the file system driver overhead, but some method of figuring out what part of the raw space has the data you want means that some form of file system is going to need to be implemented. In which case, you either implement your own, or use one of the already provided ones. Regards, David Bolt -- Team Acorn: http://www.distributed.net/ OGR-P2 @ ~100Mnodes RC5-72 @ ~15Mkeys SUSE 10.1 32bit | openSUSE 10.2 32bit | openSUSE 10.3 32bit | openSUSE 11.0a1 SUSE 10.1 64bit | openSUSE 10.2 64bit | openSUSE 10.3 64bit RISC OS 3.6 | TOS 4.02 | openSUSE 10.3 PPC | RISC OS 3.11 -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org
On Wednesday 13 February 2008 07:11, David Bolt wrote:
On Wed, 13 Feb 2008, Carlos E. R. wrote:-
The Wednesday 2008-02-13 at 13:51 +0200, Dirk Moolman wrote:
Sorry, let me explain.
We are using Oracle. Oracle uses filesystems to create datafiles in, for example it will create files like:
/oradata01/system01.dbf /oradata02/users01.dbf
Is that mandatory? Can it not access a mass-storage device directly?
Now if /oradata02 (a new filesystem I created) points to the device /dev/sda, instead of /dev/sda1 (a partition on sda), will this be a problem ?
As far as I know, which isn't that much, there should be no problem.
There isn't. Reiserfs, ext2/3 and XFS all support file systems that use the entire device, not just a partition. While I haven't tried it, JFS may also support it as well.
Why wouldn't it work? The I/O model is identical whether addressing a slice / partition or the whole disk. Are there file systems that access multiple partitions? Using a separate one for a journal, maybe?
It is also possible to write a single file to a device, without filesystem (raw). I understand some databases did/do that. Being a entire device there is no problem with partition limits and overwriting another partition space, and it is supposed to be faster.
Well, it's not going to have the file system driver overhead, but some method of figuring out what part of the raw space has the data you want means that some form of file system is going to need to be implemented. In which case, you either implement your own, or use one of the already provided ones.
Well, some DBMSs do in fact manage their space from a uniform "file," which may be a device or a conventional file. Such DBMSs will probably perform better when they use a device directly. But if the DBMS uses multiple files, as MySQL does, e.g., then this is not an option. I'm a lightweight when it comes to RDBMS, but I thought Oracle could use disks directly, avoiding file-system overhead.
Regards, David Bolt
Randall Schulz -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org
On Wed, 13 Feb 2008, Randall R Schulz wrote:-
On Wednesday 13 February 2008 07:11, David Bolt wrote:
There isn't. Reiserfs, ext2/3 and XFS all support file systems that use the entire device, not just a partition. While I haven't tried it, JFS may also support it as well.
Why wouldn't it work? The I/O model is identical whether addressing a slice / partition or the whole disk.
I didn't say it wouldn't, I said it may because I hadn't tested it.
Are there file systems that access multiple partitions? Using a separate one for a journal, maybe?
Ext3 can save the journal elsewhere by using the option: -J device=/path/to/journal/device when creating the file system. Reiserfs can do the same by using the option: --journal-device /path/to/journal/file Xfs can save the metadata log to another device using the option: -l logdev=/path/to/metadata/log
Well, some DBMSs do in fact manage their space from a uniform "file," which may be a device or a conventional file. Such DBMSs will probably perform better when they use a device directly. But if the DBMS uses multiple files, as MySQL does, e.g., then this is not an option.
I'm a lightweight when it comes to RDBMS, but I thought Oracle could use disks directly, avoiding file-system overhead.
I've no idea about that. I've never used Oracle, so never needed to know. Regards, David Bolt -- Team Acorn: http://www.distributed.net/ OGR-P2 @ ~100Mnodes RC5-72 @ ~15Mkeys SUSE 10.1 32bit | openSUSE 10.2 32bit | openSUSE 10.3 32bit | openSUSE 11.0a1 SUSE 10.1 64bit | openSUSE 10.2 64bit | openSUSE 10.3 64bit RISC OS 3.6 | TOS 4.02 | openSUSE 10.3 PPC | RISC OS 3.11 -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org
David Bolt wrote:
On Wed, 13 Feb 2008, Carlos E. R. wrote:-
The Wednesday 2008-02-13 at 13:51 +0200, Dirk Moolman wrote:
Sorry, let me explain.
We are using Oracle. Oracle uses filesystems to create datafiles in, for example it will create files like:
/oradata01/system01.dbf /oradata02/users01.dbf
Now if /oradata02 (a new filesystem I created) points to the device /dev/sda, instead of /dev/sda1 (a partition on sda), will this be a problem ? As far as I know, which isn't that much, there should be no problem.
There isn't. Reiserfs, ext2/3 and XFS all support file systems that use the entire device, not just a partition. While I haven't tried it, JFS may also support it as well.
They don't specifically support it...they just don't do any sanity checking to make sure that you're NOT attempting to use the measly 1 or 2 blocks reserved for the partition table as part of your filesystem. Other than checking the name specifically, there's no way for the application to distinguish the difference between an entire disk and a partition (they're both block devices). In fact, I've even made ext2/3 and reiserfs filesystems WITHIN A REGULAR FILE out in /tmp. (Useful trick for making floppy disks years ago). -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org
On Thu, 14 Feb 2008, Aaron Kulkis wrote:-
They don't specifically support it...they just don't do any sanity checking to make sure that you're NOT attempting to use the measly 1 or 2 blocks reserved for the partition table as part of your filesystem.
Apart from the fact that it's not just 1 or 2 blocks, but is a complete cylinder (number of heads x sectors per track, usually 255 x 63), why should they do this check?
Other than checking the name specifically, there's no way for the application to distinguish the difference between an entire disk and a partition (they're both block devices).
Precisely. To use the full device you need to use -f for mkfs.xfs and mkreiserfs, while mke2fs will display a warning and requires you to explicitly say yes to do the formatting.
In fact, I've even made ext2/3 and reiserfs filesystems WITHIN A REGULAR FILE out in /tmp. (Useful trick for making floppy disks years ago).
Same here. It's also a way of creating a swap file for when there's no free space to create a new swap partition and the already existing one isn't big enough. Regards, David Bolt -- Team Acorn: http://www.distributed.net/ OGR-P2 @ ~100Mnodes RC5-72 @ ~15Mkeys SUSE 10.1 32bit | openSUSE 10.2 32bit | openSUSE 10.3 32bit | openSUSE 11.0a1 SUSE 10.1 64bit | openSUSE 10.2 64bit | openSUSE 10.3 64bit RISC OS 3.6 | TOS 4.02 | openSUSE 10.3 PPC | RISC OS 3.11 -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org
Carlos E. R. wrote:
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1
The Wednesday 2008-02-13 at 13:51 +0200, Dirk Moolman wrote:
Sorry, let me explain.
We are using Oracle. Oracle uses filesystems to create datafiles in, for example it will create files like:
/oradata01/system01.dbf /oradata02/users01.dbf
Now if /oradata02 (a new filesystem I created) points to the device /dev/sda, instead of /dev/sda1 (a partition on sda), will this be a problem ?
As far as I know, which isn't that much, there should be no problem. I assume the space is initialized (mkfs)? You can test it: write a file using the entire space in the disk (dd if=/dev/null of=...), check the kernel log.
As I recall, Oracle gets even better performance if you just use a raw disk partition -- it is capable of managing block placement on a raw disk, and gets much better perfomance than by using the disk space through a filesystem driver. That being said, if he decides to use the "whole disk" which includes the 1 or 2 blocks normally reserved for the partition table as part of his raw block device, he's just begging for data loss if the disk is ever removed from the system and put in another for some reason (hey! this partition table makes no sense -- that must be the problem -- I'll remake the first partition to use the whole disk...and wham, the first 512 - 1024 bytes are overwritten).
It is also possible to write a single file to a device, without filesystem (raw). I understand some databases did/do that. Being a entire device there is no problem with partition limits and overwriting another partition space, and it is supposed to be faster.
-- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 The Thursday 2008-02-14 at 10:54 -0500, Aaron Kulkis wrote:
As I recall, Oracle gets even better performance if you just use a raw disk partition -- it is capable of managing block placement on a raw disk, and gets much better perfomance than by using the disk space through a filesystem driver.
That being said, if he decides to use the "whole disk" which includes the 1 or 2 blocks normally reserved for the partition table as part of his raw block device, he's just begging for data loss if the disk is ever removed from the system and put in another for some reason (hey! this partition table makes no sense -- that must be the problem -- I'll remake the first partition to use the whole disk...and wham, the first 512 - 1024 bytes are overwritten).
Next step, fire the sysadmin for not reading the logbook, o not making a disk image first :-p - -- Cheers, Carlos E. R. -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.4-svn0 (GNU/Linux) iD8DBQFHtZHStTMYHG2NR9URAii9AJ9PshB4lVFGs5zv21rF+2TInKTfsACfV8K9 wUTCk8lZHRKlLeM4HyMbAFs= =fn+I -----END PGP SIGNATURE----- -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org
Carlos E. R. wrote:
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1
The Thursday 2008-02-14 at 10:54 -0500, Aaron Kulkis wrote:
As I recall, Oracle gets even better performance if you just use a raw disk partition -- it is capable of managing block placement on a raw disk, and gets much better perfomance than by using the disk space through a filesystem driver.
That being said, if he decides to use the "whole disk" which includes the 1 or 2 blocks normally reserved for the partition table as part of his raw block device, he's just begging for data loss if the disk is ever removed from the system and put in another for some reason (hey! this partition table makes no sense -- that must be the problem -- I'll remake the first partition to use the whole disk...and wham, the first 512 - 1024 bytes are overwritten).
Next step, fire the sysadmin for not reading the logbook, o not making a disk image first :-p
I've seen crazy things happen. Especially during an outage, and they're trying to get a system back up. Under stress, people start forgetting obvious things. The best thing to do is to not set up each other for failure. The drawback to using the partition table and making the whole disk part of partition one is about a penny's worth of disk space. The drawback to having a mishap because someone forgot that the disk is using the partition table space for real data -- low end is probably hundreds of dollars. -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 The Friday 2008-02-15 at 13:34 -0500, Aaron Kulkis wrote:
Next step, fire the sysadmin for not reading the logbook, o not making a disk image first :-p
I've seen crazy things happen. Especially during an outage, and they're trying to get a system back up.
Under stress, people start forgetting obvious things. The best thing to do is to not set up each other for failure.
I know. Then stick a label on the disk itself.
The drawback to using the partition table and making the whole disk part of partition one is about a penny's worth of disk space. The drawback to having a mishap because someone forgot that the disk is using the partition table space for real data -- low end is probably hundreds of dollars.
Its a whole track, I think, but don't ask me why. It is the partition table plus some space reserved, which is used in linux to store grub program (the 1st sector is not enough). In any case, you are right, it is a small space. - -- Cheers, Carlos E. R. -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.4-svn0 (GNU/Linux) iD8DBQFHtsOxtTMYHG2NR9URArgTAJ9XMGs2FR2C/KK3uIs5TdShiRakcgCfavRD C91gkeATx/ptjA0PDROy5Xs= =noiq -----END PGP SIGNATURE----- -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org
Dirk Moolman wrote:
Sorry, let me explain.
We are using Oracle. Oracle uses filesystems to create datafiles in, for example it will create files like:
/oradata01/system01.dbf /oradata02/users01.dbf
Now if /oradata02 (a new filesystem I created) points to the device /dev/sda, instead of /dev/sda1 (a partition on sda), will this be a problem ?
It formatted and mounted fine, without any problems, and Oracle is ok with the space. I just don't want to run into problems further down the line, so I just want to make sure it is ok like this.
With some Unix systems you have to be careful with your device partitions, and your offsets that you use, but I don't have much experience on Linux, and just want to confirm that the above setup will be ok.
If you're running oracle, surely you're running it on SLES? Joe -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org
-----Original Message----- From: Sloan [mailto:joe@tmsusa.com] Sent: 13 February 2008 08:19 PM To: opensuse@opensuse.org Subject: Re: [opensuse] Use entire disk, and not a partition
Sorry, let me explain.
We are using Oracle. Oracle uses filesystems to create datafiles in, for example it will create files like:
/oradata01/system01.dbf /oradata02/users01.dbf
Now if /oradata02 (a new filesystem I created) points to the device /dev/sda, instead of /dev/sda1 (a partition on sda), will this be a problem ?
It formatted and mounted fine, without any problems, and Oracle is ok with the space. I just don't want to run into problems further down
Dirk Moolman wrote: the
line, so I just want to make sure it is ok like this.
With some Unix systems you have to be careful with your device partitions, and your offsets that you use, but I don't have much experience on Linux, and just want to confirm that the above setup will be ok.
If you're running oracle, surely you're running it on SLES?
That is correct yes - SLES9 service pack 3 *** Disclaimer *** The information contained in this e-mail is confidential and legally privileged and is intended solely for the addressee and to others who have the authority to receive it. Access to this e-mail by anyone else is unauthorized and as such, any disclosure, copying, distribution or any action taken or omitted in reliance on it is unlawful. If you have received this e-mail in error, please notify the sender immediately. The views expressed in this e-mail are the views of the individual sender and should in no way be construed as the views of the Company. The Company is not liable to ensure that outgoing e-mails are virus-free. The Company is not liable, should information or data, for whatever reason, be corrupted or fail to reach its intended addressee. The Company is not liable for any loss or damage of whatsoever nature and howsoever arising resulting from the opening or the use of the information in this e-mail, including its attachments and links. The sender of this e-mail is subject to and bound by the terms and conditions of Company+IBk-s Electronic Communications Usage Policy. -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org
Dirk Moolman wrote:
Sorry, let me explain.
We are using Oracle. Oracle uses filesystems to create datafiles in, for example it will create files like:
/oradata01/system01.dbf /oradata02/users01.dbf
Now if /oradata02 (a new filesystem I created) points to the device /dev/sda, instead of /dev/sda1 (a partition on sda), will this be a problem ?
Having administrated Oracle servers, your best bet is to still go through the partition table. Create /sd_1 to use the whole disk if you want, but in general, trying to use the first 1 or 2 blocks (I forget which) that are reserved for the partition table is asking for headaches and/or data corruption if the disk is removed and given to someone else to do something with if someone forgets to tell them that the disk doesn't have a partition table. Mistakes as in DATA LOSS by overwriting the block(s) normally used by a partition table.
It formatted and mounted fine, without any problems, and Oracle is ok with the space. I just don't want to run into problems further down the line, so I just want to make sure it is ok like this.
With some Unix systems you have to be careful with your device partitions, and your offsets that you use, but I don't have much experience on Linux, and just want to confirm that the above setup will be ok.
Dirk
-----Original Message----- From: David Bolt [mailto:bcrafhfr@davjam.org] Sent: 13 February 2008 01:03 PM To: opensuse@opensuse.org Subject: Re: [opensuse] Use entire disk, and not a partition
On Wed, 13 Feb 2008, Dirk Moolman wrote:-
If you have a disk, let's say /dev/sda, and instead of creating partitions on the disk, for example /dev/sda1, you use the entire disk, format it, and allocate it to an application - will this cause any problems ?
What do you mean by "allocate it to an application" ?
Do you mean something like creating a file system on the device, mounting it on /srv/www and leaving it just for Apache2? If so, it shouldn't. If not, how about giving a concrete example of what you mean?
In short: the application points to and uses /dev/sda (which is mounted), instead of /dev/sda1.
Unless the application is specifically manipulating devices, it's not going to be using /dev/sda but will use whatever directory /dev/sda uses as the mount point.
Regards, David Bolt
-- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org
Dirk Moolman wrote:
If you have a disk, let's say /dev/sda, and instead of creating partitions on the disk, for example /dev/sda1, you use the entire disk, format it, and allocate it to an application - will this cause any problems ?
Yes...you don't have a partition table. While Linux can use that...you're really violating all kinds of standards. All that for the purpose of saving 1 block or 2 blocks (512 - 1024 bytes) is normally not a good tradeoff. I would consider this sort of thing appropriate for a deep-space probe which will never return to Earth MUCH more than any disk drive which is going to stay here, and has a real chance (say for data recovery or whatever) get thrown into another system. This is the kind of thing which causes potential problems which take hours to resolve because you forget something...or worse, someone uses fdisk to re-create the partition table, and overwrites the first 1k of your filesystem
In short: the application points to and uses /dev/sda (which is mounted), instead of /dev/sda1.
Applications don't point to /dev/sd_anything, (or any other block device for that matter) unless you are talking about an Oracle or other database using the disk in raw mode. Applications use normal files within a filesystem, not partitions. Even Oracle should use, say /dev/sdc1, not /dev/sdc. Using the space reserved for the partition table is just begging for data loss if the disk is ever removed and put into another computer, for whatever reason. -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 The Thursday 2008-02-14 at 10:41 -0500, Aaron Kulkis wrote:
Yes...you don't have a partition table. While Linux can use that...you're really violating all kinds of standards. All that for the purpose of saving 1 block or 2 blocks (512 - 1024 bytes) is normally not a good tradeoff.
I would consider this sort of thing appropriate for a deep-space probe which will never return to Earth MUCH more than any disk drive which is going to stay here, and has a real chance (say for data recovery or whatever) get thrown into another system.
X'-) I have seen partitionless usb memory sticks somewhere. As for the clueless technician overwriting the non existing partition table... shame and wrath unto him/her! :-P - -- Cheers, Carlos E. R. -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.4-svn0 (GNU/Linux) iD8DBQFHtGjmtTMYHG2NR9URAtQgAJ45jlJrhSLl9ZuKVq8hVTSlzdOv1gCfbhkW JfTCjprjZl+gVc53+P6bc5g= =Us7+ -----END PGP SIGNATURE----- -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org
Carlos E. R. wrote:
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1
The Thursday 2008-02-14 at 10:41 -0500, Aaron Kulkis wrote:
Yes...you don't have a partition table. While Linux can use that...you're really violating all kinds of standards. All that for the purpose of saving 1 block or 2 blocks (512 - 1024 bytes) is normally not a good tradeoff.
I would consider this sort of thing appropriate for a deep-space probe which will never return to Earth MUCH more than any disk drive which is going to stay here, and has a real chance (say for data recovery or whatever) get thrown into another system.
X'-)
I have seen partitionless usb memory sticks somewhere.
As for the clueless technician overwriting the non existing partition table... shame and wrath unto him/her! :-P
Hey, everybody is a newbie at some point..and even relatively experienced admins who is new to the idea of an Oracle database using raw partitions could get caught by this. Frankly, the substantial increase in risk isn't worth 512 - 1024 BYTES of disk space -- it also completely eliminates the chance of scavanging unused disk space at the end of the disk for other purposes (either another table, crash-dump storage, or whatever) -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org
participants (9)
-
Aaron Kulkis -
Carlos E. R. -
David Bolt -
Dirk Moolman -
K.R. Foley -
Ken Schneider -
Philipp Thomas -
Randall R Schulz -
Sloan