On Thu, Apr 08, 2010 at 01:14:42PM -0700, K. Macy wrote: > Hi Alexandr, Hi Kip,
> > - How much memory do you have? 4Gb. Applications consume a lot of memory, is partially used swap (~1Gb, but without active i/o). We have planned increase in memory to 16G > > - What are your ARC settings? Settings is default, that recommended for amd64 kernel. But I am not assured that it is optimal. Thus sysctl variables are automatically sets to: vfs.zfs.arc_max ~800Mb vfs.zfs.arc_mim ~128Mb Now the next reboot was required. Together with which following settings have been made: vm.kmem_size=2048M vfs.zfs.arc_max=1536M vfs.zfs.arc_min=1024M vfs.zfs.vdev.cache.size=64M Let's look, as it will affect. However there is confidence that no problem at a size of ARC. Even at 200Mb ARC, productivity should not fall so strongly. > > Thanks, > Kip > > On Thu, Apr 8, 2010 at 8:32 AM, Alexandr D. Sergeev <[email protected]> wrote: > > Hi, all! > > > > There are problems with a server on FreeBSD 7.2 CURRENT (6 Jul 2009), > > carrying out the task of mail server SMTP, IMAP. > > > > Messages are stored in maildirs on file system ZFS (mirror of 2 SAS 3k > > drives). > > Dovecot is used as IMAP server. > > > > After reboot the system works perfectly, however, somewhere in a month, at > > the same load, arise periodic long delays at opening of new letters. > > > > Judging by output iostat -x -w 1, during these moments the disk subsystem > > is strongly loaded. > > %busy disks comes nearer to 100 %. Readings nearby 300 per sec prevail. and > > approx. 10MBytes per sec. > > > > Somebody can advise, what diagnostics needed, for understanding of the > > reason of problems? > > > > There is an opinion that a problem with ZFS. > > > > Probably, it does not have enough memory. Because during the periods of > > occurrence of a problem, ARC is have less 300MB: > > > > vmstat -m > > ... > > solaris 1245732 274745K - 25872717949 > > 16,32,64,128,256,512,1024,2048,4096 > > ... > > > > Or it is bug of ZFS implementation. > > > > -- > > Best regards, > > Alexandr D.Sergeev > > _______________________________________________ > > [email protected] mailing list > > http://lists.freebsd.org/mailman/listinfo/freebsd-performance > > To unsubscribe, send any mail to > > "[email protected]" > > -- Best regards, Alexandr D.Sergeev _______________________________________________ [email protected] mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-performance To unsubscribe, send any mail to "[email protected]"
