On 6/27/11 8:04 AM, Paul Anderson wrote: > One thing this thread indicates is the need for a warning in mkfs.xfs > - according to several developers, there is, I think, linear increase > in allocation time to number of allocation groups. > > It would be helpful for the end user to simply issue a warning stating > this when the AG count seems high with a brief explanation as to why > it seems high. I would allow it, but print the warning. Even a > simple linear check like agroups>500 should suffice for "a while". I disagree. There are all sorts of ways a user can shoot themselves in the foot with unix commands. Detecting and warning about all of them is a fool's errand. ====================================== = Warning! mkfs.xfs detected insane = = option specification. Cancel? = = = = [ OK ] [ Cancel ] = ====================================== -Eric > Paul > > On Mon, Jun 27, 2011 at 4:55 AM, Stan Hoeppner <stan@xxxxxxxxxxxxxxxxx> wrote: >> On 6/26/2011 11:14 PM, Marcus Pereira wrote: >>> Em 27-06-2011 00:33, Stan Hoeppner escreveu: >>>> >>>> I recommend 3 changes, one of which I previously mentioned: >>>> >>>> 1. Use 8 mirror pairs instead of 4 >>>> 2. Don't use striping. Make an mdraid --linear device of the 8 mirrors >>>> 3. Format with '-d agcount=32' which will give you 4 AGs per spindle >>>> >>>> Test this configuration and post your results. >>> >>> I am thanks for all advices. I will make the tests and post, may take >>> some time. >>> >>> About all other messages. My system may not be a Ferrari but its not a >>> Volks. I certainly do not have that many HDs in fiber channel, but the >>> sever is a dual core Xeon 6 cores with HT. Linux sees a total of 24 >>> cores, total RAM is 24GB. The HDs are all SAS 15Krpm and the system runs >>> on SSD. They are dedicated to handle the maildir files and I have >>> several of those servers running nicely. >>> But I don’t want to make the thread about my system larger. >> >> So you do or don't have the excessive head seek problem you previously >> mentioned? If not then use the mkfs.xfs defaults. >> >>> Yes, I don’t know much about XFS and Allocation groups, thanks for you >>> all to help me a bit. >> >> You're welcome. Google should turn up a decent amount of information >> about XFS allocation groups if you're interested in further reading. >> >>> At the end the reason why I opened the thread it the error and the >>> developers should take some care about that. >> >>> Ok, no reason to use that many agcount but giving a "mkfs.xfs: pwrite64 >>> failed: No space left on device" error for me stills seems a bug. >> >> The definition of a software bug stipulates incorrect or unexpected >> program behavior. Error messages aren't bugs unless the wrong error >> message is returned for a given fault condition, or no error is returned >> when one should be. >> >> Are you stipulating that the above isn't the correct error message for >> the fault condition? Or do you simply not understand the error message? >> If the latter, maybe you should simply ask what that error means before >> saying the error message is a bug. :) >> >> -- >> Stan >> >> _______________________________________________ >> xfs mailing list >> xfs@xxxxxxxxxxx >> http://oss.sgi.com/mailman/listinfo/xfs >> > > _______________________________________________ > xfs mailing list > xfs@xxxxxxxxxxx > http://oss.sgi.com/mailman/listinfo/xfs > _______________________________________________ xfs mailing list xfs@xxxxxxxxxxx http://oss.sgi.com/mailman/listinfo/xfs
