Hello Rayson, Tuesday, October 2, 2007, 8:56:09 PM, you wrote:
RH> 1) Modern DBMSs cache database pages in their own buffer pool because RH> it is less expensive than to access data from the OS. (IIRC, MySQL's RH> MyISAM is the only one that relies on the FS cache, but a lot of MySQL RH> sites use INNODB which has its own buffer pool) RH> 2) Also, direct I/O is faster because it avoid double buffering. I doubt its buying you much... However on UFS if you go with direct IO, you allow concurent writes to the same file and you disable read-aheads - I guess it's buying you much more in most cases than eliminating double buffering. Now the question is - if application is usingi directio() call - what happens if underlying fs is zfs? -- Best regards, Robert Milkowski mailto:[EMAIL PROTECTED] http://milek.blogspot.com _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
