Hello Neil, Thursday, August 10, 2006, 7:02:58 PM, you wrote:
NP> Robert Milkowski wrote: >> Hello Matthew, >> >> Thursday, August 10, 2006, 6:55:41 PM, you wrote: >> >> MA> On Thu, Aug 10, 2006 at 06:50:45PM +0200, Robert Milkowski wrote: >> >>>>btw: wouldn't it be possible to write block only once (for synchronous >>>>IO) and than just point to that block instead of copying it again? >> >> >> MA> We actually do exactly that for larger (>32k) blocks. >> >> Why such limit (32k)? NP> By experimentation that was the cutoff where it was found to be NP> more efficient. It was recently reduced from 64K with a more NP> efficient dmu-sync() implementaion. I do not understand - why in some cases with smaller block writing block twice could be actually faster than doing it once every time? I definitely am missing something here... NP> Feel free to experiment with the dynamically changable tunable: NP> ssize_t zfs_immediate_write_sz = 32768; I will :) By dynamic you mean it works right a way without any need to umount/mount and export/import? -- Best regards, Robert mailto:[EMAIL PROTECTED] http://milek.blogspot.com _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
