[yast-devel] fulltime Y2DEBUG=1???
I have a customer who is asking if it's OK to set Y2DEBUG=1 all the time: When we encounter SLES media problem, one of the first things SuSE engineers ask us to do is reproduce with Y2DEBUG=1 on the kernel commandline. We were thinking about always having this media feature enabled going forward. Can we ask SuSE engineers if there is any cause for concern in doing this? ---- Roberto Angelino Dedicated Partner Engineer Developer Support (310) 529-3527 -- To unsubscribe, e-mail: yast-devel+unsubscribe@opensuse.org To contact the owner, e-mail: yast-devel+owner@opensuse.org
Hi Roberto, in principle, there is nothing that prevents always logging in the debug mode. However, you should be aware that the amount of data being logged is huge. This has following implications: - as the logs are stored in ramdisk during installation, the memory requirements for installation may go up slightly - the amount of data written to the log may hit the installation time, especially in 2nd stage (writing directly to disk) - (probably worst) the log will need to rotate - meaning that at the end of the installation, the logs from the beginning may not be available any more Especially the last one may mean that in the end you don't resolve customer's problem, but even make it worse for us to obtain the right part of the log. HTH, Jiri On 05/02/2013 09:32 PM, Roberto Angelino wrote:
I have a customer who is asking if it's OK to set Y2DEBUG=1 all the time:
When we encounter SLES media problem, one of the first things SuSE engineers ask us to do is reproduce with Y2DEBUG=1 on the kernel commandline. We were thinking about always having this media feature enabled going forward. Can we ask SuSE engineers if there is any cause for concern in doing this?
---- Roberto Angelino Dedicated Partner Engineer Developer Support (310) 529-3527
-- Regards, Jiri Srain Project Manager --------------------------------------------------------------------- SUSE LINUX, s.r.o. e-mail: jsrain@suse.com Lihovarska 1060/12 tel: +420 284 084 659 190 00 Praha 9 fax: +420 284 084 001 Czech Republic http://www.suse.com -- To unsubscribe, e-mail: yast-devel+unsubscribe@opensuse.org To contact the owner, e-mail: yast-devel+owner@opensuse.org
On 05/03/2013 09:07 AM, Jiri Srain wrote:
Hi Roberto,
in principle, there is nothing that prevents always logging in the debug mode. However, you should be aware that the amount of data being logged is huge. This has following implications:
- as the logs are stored in ramdisk during installation, the memory requirements for installation may go up slightly
- the amount of data written to the log may hit the installation time, especially in 2nd stage (writing directly to disk)
- (probably worst) the log will need to rotate - meaning that at the end of the installation, the logs from the beginning may not be available any more
Especially the last one may mean that in the end you don't resolve customer's problem, but even make it worse for us to obtain the right part of the log.
And I have some more "why not to do that": - The amount of logs in debug mode comparing to normal mode is that much bigger that is almost impossible to find what you are looking for when looking for possible errors reported in logs. - It's true that I don't have the `data` but I don't think most of the time Y2DEBUG is required by SUSE engineers. Frankly, I personally don't want it almost ever. - Debugging definitely slows down the execution time as the application is always waiting for disk / memory / swap to write the log, especially on some HW such as S/390. Bye Lukas -- Lukas Ocilka, Cloud & Systems Management Department SUSE LINUX s.r.o., Praha -- To unsubscribe, e-mail: yast-devel+unsubscribe@opensuse.org To contact the owner, e-mail: yast-devel+owner@opensuse.org
On Thu, May 02, Roberto Angelino wrote:
I have a customer who is asking if it's OK to set Y2DEBUG=1 all the time:
When we encounter SLES media problem, one of the first things SuSE engineers ask us to do is reproduce with Y2DEBUG=1 on
Do they? I am surprised about that. I cannot remember to have requested logs with Y2DEBUG set at all the last some years. In fact since I do sometimes get logs with Y2DEBUG=1 (no idea why), I even use scripts to throw away the added junk of Y2DEBUG to get usable log files. Maybe this is simply a ballot point at NCC? If yes, maybe we should try to remove that. What about others? Do we really regularly need logs with Y2DEBUG=1?
the kernel commandline. We were thinking about always having this media feature enabled going forward. Can we ask SuSE engineers if there is any cause for concern in doing this?
The biggest problem is that logs may get overwritten round-robin-wise if they tend to get too big. Especially in storage area this can be fatal, when a problem possibly related to storage (e.g. bootloader setup, fstab entries) show up at end of install and log of storage setup (which happens at begin of install) is already overwritten. Bye, Thomas Fehr -- Thomas Fehr, SuSE Linux Products GmbH, Maxfeldstr. 5, 90409 Nuernberg, Germany GF: Jeff Hawn, Jennifer Guild, Felix Imendörffer, HRB 16746 (AG Nürnberg) Tel: +49-911-74053-0, Fax: +49-911-74053-482, Email: fehr@suse.de GPG public key available. -- To unsubscribe, e-mail: yast-devel+unsubscribe@opensuse.org To contact the owner, e-mail: yast-devel+owner@opensuse.org
Dne 3.5.2013 11:08, Thomas Fehr napsal(a):
What about others? Do we really regularly need logs with Y2DEBUG=1?
As for me, I have needed debug logs just few times so far. And as the others pointed out, the huge amount of details makes search for relevant data much worse. I usually ask to use Shift-F7 magic combination (unfortunately available only in Qt UI) to switch debug on/off dynamically at runtime if I really need debug log. This way you can get details just in a specific point, not for the whole yast run. So you have details you need and yet small log file at the same time. Another reason for NOT doing this is a bugzilla attachment size limit. I don't know what's the current limit, but it can deny to upload too big logs... -- Ladislav Slezák Appliance department / YaST Developer Lihovarská 1060/12 190 00 Prague 9 / Czech Republic tel: +420 284 028 960 lslezak@suse.com SUSE -- To unsubscribe, e-mail: yast-devel+unsubscribe@opensuse.org To contact the owner, e-mail: yast-devel+owner@opensuse.org
On Friday 03 May 2013 11:08:50 Thomas Fehr wrote:
What about others? Do we really regularly need logs with Y2DEBUG=1?
Zypp never needs Y2DEBUG=1. For me personally a Y2DEBUG log is too bloated. I usually strip those lines before looking into the log. Otherwise I can hardly read it. -- cu, Michael Andres +------------------------------------------------------------------+ Key fingerprint = 2DFA 5D73 18B1 E7EF A862 27AC 3FB8 9E3A 27C6 B0E4 +------------------------------------------------------------------+ Michael Andres SUSE LINUX Products GmbH, Development, ma@suse.de GF:Jeff Hawn,Jennifer Guild,Felix Imendörffer, HRB16746(AG Nürnberg) Maxfeldstrasse 5, D-90409 Nuernberg, Germany, ++49 (0)911 - 740 53-0 +------------------------------------------------------------------+ -- To unsubscribe, e-mail: yast-devel+unsubscribe@opensuse.org To contact the owner, e-mail: yast-devel+owner@opensuse.org
participants (6)
-
Jiri Srain -
Ladislav Slezak -
Lukas Ocilka -
Michael Andres -
Roberto Angelino -
Thomas Fehr