Re: ZFS - abysmal performance with samba since upgrade to 8.2-RELEASE

On Thu, Feb 24, 2011 at 8:55 AM, Jeremy Chadwick
<freebsd@xxxxxxxxxxxxxxxx> wrote:


 # Set TXG write limit to a lower threshold.  This helps "level out"
 # the throughput rate (see "zpool iostat").  A value of 256MB works well
 # for systems with 4GB of RAM, while 1GB works well for us w/ 8GB on
 # disks which have 64MB cache.
 vfs.zfs.txg.write_limit_override=1073741824



Sorry if you have said this before, but could you elaborate a bit
about this number? For instance, how much does the cache on the disk
has to say.
In my case: 3x1.5TB raidz with WD15EADS-00R6B0 which has 32MB cache
and 12GB memory. What would you recommend and why.

--
chs,
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