Re: [PERFORM] Direct I/O issues

2006-11-23 Thread Tom Lane
Greg Smith [EMAIL PROTECTED] writes: The results I get now look fishy. There are at least two things wrong with this program: * It does not respect the alignment requirement for O_DIRECT buffers (reportedly either 512 or 4096 bytes depending on filesystem). * It does not check for errors (if

Re: [PERFORM] Direct I/O issues

2006-11-23 Thread Greg Smith
On Thu, 23 Nov 2006, Tom Lane wrote: * It does not check for errors (if it had, you might have realized the other problem). All the test_fsync code needs to check for errors better; there have been multiple occasions where I've run that with quesiontable input and it didn't complain, it

Re: [PERFORM] Direct I/O issues

2006-11-23 Thread Bruce Momjian
Greg Smith wrote: On Thu, 23 Nov 2006, Tom Lane wrote: * It does not check for errors (if it had, you might have realized the other problem). All the test_fsync code needs to check for errors better; there have been multiple occasions where I've run that with quesiontable input and it