[opensuse] Btrfs and SSD
I'm about do do an install of openSUSE 13.2 on a new Samsung 850 Pro SSD. Opinions on the internet about both the shape of the earth and the wisdom of using various filesystems on SSDs differ. My intention is to use conventional partitioning and accept the defaults of btrfs and xfs for / and /home respectively. I don't want to use LVM for a number of reasons, chiefly because this has to co-exist with a Ubuntu system (partially on the same drive) because I support family who use Ubuntu and Kylin (the Ubuntu flavor for Chinese speakers). I'm reasonably familiar with SUSE, having used it from 9.1 until I got discouraged with it somewhere around 10.2 and KDE 4.0. There are some warnings out there about using btrfs on SSDs due to excessive writes. Does anyone here have any experience or wisdom on this to share? Will the installer recognize that it is installing on an SSD and make the appropriate changes to fstab, or will I have to do it by hand later? On ext4 filesystems I've been adding noatime to SSD mounts. Is this recommended for btrfs and xfs? -- Paul Carlson N 39.4448 W 119.7503 Elv. 1360m -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org
On Sat, Jan 24, 2015 at 8:19 AM, Paul Carlson
There are some warnings out there about using btrfs on SSDs due to excessive writes. Does anyone here have any experience or wisdom on this to share? Will the installer recognize that it is installing on an SSD and make the appropriate changes to fstab, or will I have to do it by hand later?
Before a btrfs filesystem is mounted, the value of /sys/block/sdX/queue/rotational is checked. If it is zero, the filesystem is mounted with the "ssd" mount option automatically, which provides for SSD optimized behavior [1].
On ext4 filesystems I've been adding noatime to SSD mounts. Is this recommended for btrfs and xfs?
From what I have read, atime or the default relatime option can cause the COW behavior of btrfs to cause excessive duplication of metadata blocks, which can impact snapshots. Mounting a filesystem with noatime can break some programs [2].
You might be interested in the example mount options on the Arch Linux page for btrfs for additional optimizations [3]. [1] https://btrfs.wiki.kernel.org/index.php/Mount_options [2] http://lwn.net/Articles/499293/ [3] https://wiki.archlinux.org/index.php/Btrfs#Mount_options Brandon Vincent -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org
Le 24/01/2015 16:19, Paul Carlson a écrit :
I'm about do do an install of openSUSE 13.2 on a new Samsung 850 Pro SSD. Opinions on the internet about both the shape of the earth and the wisdom of using various filesystems on SSDs differ.
I'm also moving to ssds given they have 3 years garanty, I do not change anthing and install the default yast provide. given the speed the prices get lower, I will probably change my disk before it fail. anyway I have a pretty good backup strategy :-) jdd -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org
On Sat, 24 Jan 2015 07:19:30 Paul Carlson wrote:
I'm about do do an install of openSUSE 13.2 on a new Samsung 850 Pro SSD. Opinions on the internet about both the shape of the earth and the wisdom of using various filesystems on SSDs differ.
My intention is to use conventional partitioning and accept the defaults of btrfs and xfs for / and /home respectively. I don't want to use LVM for a number of reasons, chiefly because this has to co-exist with a Ubuntu system (partially on the same drive) because I support family who use Ubuntu and Kylin (the Ubuntu flavor for Chinese speakers).
I'm reasonably familiar with SUSE, having used it from 9.1 until I got discouraged with it somewhere around 10.2 and KDE 4.0.
There are some warnings out there about using btrfs on SSDs due to excessive writes. Does anyone here have any experience or wisdom on this to share? Will the installer recognize that it is installing on an SSD and make the appropriate changes to fstab, or will I have to do it by hand later?
On ext4 filesystems I've been adding noatime to SSD mounts. Is this recommended for btrfs and xfs?
I've just moved my oS 13.1 system to the Samsung 850 Pro SSD. Samsung's documentation indicates that their native optimisation tool only supports trim on ext4. In a recent thread on this topic (I was asking for advice/info before doing the migration) Greg Freemeyer cautioned against relying too heavily on current filesystems' native trim implementations, preferring rather to use batched trim. Samsung's "magician" CLI utility does this for their SSD's, most likely using the drive's native firmware functionality. I don't trust btrfs at this point in time - I've been bitten once already where the root filesystem (i.e. /) became corrupted and was unable to be repaired using any tools that I had available to me. The result was that / was mounted read-only at every boot, meaning no updates could be performed, no logs could be written and no configuration changes could be saved. I ended up having to do a complete reinstall (which was done using ext4). Now, this might have been a one-off, but once bitten...etc. For me, I chose to take Samsung's advice and stick with ext4. YMMV. Rodney. -- ============================================================== Rodney Baker VK5ZTV rodney.baker@iinet.net.au ============================================================== -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org
Am Samstag, 24. Januar 2015 16:19 CET, Paul Carlson
There are some warnings out there about using btrfs on SSDs due to excessive writes. Does anyone here have any experience or wisdom on
this to share? Will the installer recognize that it is installing on an SSD and make the appropriate changes to fstab, or will I have to do it by hand later?
FWIW, I've been using openSUSE with root on SSD for several years, now. I think I started with 12.3 or 12.2. btrfs never caused me trouble because of the SSD and I never lost data. I did end up once with a situation where I had accidentally copied a lot of data to my root folder. A few days later, I noticed that / was full. I found the files and deleted them. But the file system was still full. That's when I found a drawback of the snapshots ... Took me some time to figure out what was going on. Afterwards, it was simple to write a script that located the snapshots in question (just by looking for one of the files inside), mounting it RW and deleting the huge folder. Other than that, I never had problems or performance issues and I've been using this computer 2-4h every day. That said, I'm replacing my hardware every 3-4 years. So it doesn't die on me which means I have no experience with how btrfs fares when the drive is slowly failing beneath it. I also probably never got close to the physical write-count limits of the SSD; I buy them big enough (60GB), so they are usually max. 50% full. Regards, -- Aaron "Optimizer" Digulla a.k.a. Philmann Dark "It's not the universe that's limited, it's our imagination. Follow me and I'll show you something beyond the limits." http://blog.pdark.de/ -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org
On 01/26/2015 08:57 AM, Aaron Digulla wrote:
But the file system was still full. That's when I found a drawback of the snapshots ... Took me some time to figure out what was going on. Afterwards, it was simple to write a script that located the snapshots in question (just by looking for one of the files inside), mounting it RW and deleting the huge folder.
BTDT with BytrFS on rotating rust. Yes I deleted it. But then I went into config and disabled snapshotting. As far as i could see, the major benefit of snapshotting on RootFS was rolling back zypper updates.
I also probably never got close to the physical write-count limits of the SSD; I buy them big enough (60GB), so they are usually max. 50% full.
Since a basic system is only about 20G that's a sound approach. Oh, but then I have /usr/share and /var and /tmp on separate file systems.
Other than that, I never had problems or performance issues and I've been using this computer 2-4h every day.
I've been running BtrFS on ROOT on one machine or another for most of the life if 13.1. I had a a problem with it on /home but never on the RootFS. Except, as above with snapshotting filling it up! -- /"\ \ / ASCII Ribbon Campaign X Against HTML Mail / \ -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org
There's a special on from a Calgary firm, memory Express, today. A 1T SD for less than $100. http://www.memoryexpress.com/Products/MX44769?utm_source=eFlyer&utm_medium=email&utm_campaign=Jan2015_24hrDailyDeal-Jan26 It makes me wonder ... That, mirrored to my rotating 1T ... -- /"\ \ / ASCII Ribbon Campaign X Against HTML Mail / \ -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org
On 01/26/2015 09:13 AM, Anton Aylward wrote:
There's a special on from a Calgary firm, memory Express, today. A 1T SD for less than $100.
Correction, its 'flash accelerated' not a pure SSD. -- /"\ \ / ASCII Ribbon Campaign X Against HTML Mail / \ -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org
Le 26/01/2015 15:16, Anton Aylward a écrit :
On 01/26/2015 09:13 AM, Anton Aylward wrote:
There's a special on from a Calgary firm, memory Express, today. A 1T SD for less than $100.
Correction, its 'flash accelerated' not a pure SSD.
yes, hybrid I could get a Kingston HyperX 3K, 240 Go, SATA III http://www.topachat.com/pages/detail2_cat_est_micro_puis_rubrique_est_w_ssd_... but for just under €100, extremely fast, recommended :-) jdd -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org
participants (6)
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Aaron Digulla -
Anton Aylward -
Brandon Vincent -
jdd -
Paul Carlson -
Rodney Baker