From: Gregory Shaw <[EMAIL PROTECTED]> Sender: [EMAIL PROTECTED] To: Mike Gerdts <[EMAIL PROTECTED]> Cc: ZFS filesystem discussion list <zfs-discuss@opensolaris.org>, [EMAIL PROTECTED] Subject: Re: [zfs-discuss] ZFS and databases Date: Thu, 11 May 2006 13:15:48 -0600
Regarding directio and quickio, is there a way with ZFS to skip the system buffer cache? I've seen big benefits for using directio when the data files have been segregated from the log files. Were the benefits coming from extra concurrency (no single writter lock) or avoiding the extra copy to page cache or from too much readahead that is not used before pages need to be recycled. ZFS already has the concurrency. The page cache copy is really rather cheap and I assert somewhat necessary to insure data integrity The extra readahead is somewhat of a bug in UFS (read 2 pages get a maxcontig chunk (1MB)). ZFS is new, conventional wisdom, may or may not apply. -r _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
