On Mar 20, 2008, at 11:07 AM, Bob Friesenhahn wrote: > On Thu, 20 Mar 2008, Mario Goebbels wrote: > >>> Similarly, read block size does not make a >>> significant difference to the sequential read speed. >> >> Last time I did a simple bench using dd, supplying the record size as >> blocksize to it instead of no blocksize parameter bumped the mirror >> pool >> speed from 90MB/s to 130MB/s. > > Indeed. However, as an interesting twist to things, in my own > benchmark runs I see two behaviors. When the file size is smaller > than the amount of RAM the ARC can reasonably grow to, the write block > size does make a clear difference. When the file size is larger than > RAM, the write block size no longer makes much difference and > sometimes larger block sizes actually go slower.
in that case .. try fixing the ARC size .. the dynamic resizing on the ARC can be less than optimal IMHO --- .je _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
