| From: | Zdenek Kotala <Zdenek(dot)Kotala(at)Sun(dot)COM> |
|---|---|
| To: | Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> |
| Cc: | Gregory Stark <stark(at)enterprisedb(dot)com>, Simon Riggs <simon(at)2ndquadrant(dot)com>, pgsql-hackers(at)postgresql(dot)org |
| Subject: | Re: Page-at-a-time Locking Considerations |
| Date: | 2008-02-06 19:36:18 |
| Message-ID: | 47AA0C32.1030807@sun.com |
| Views: | Raw Message | Whole Thread | Download mbox | Resend email |
| Thread: | |
| Lists: | pgsql-hackers |
Tom Lane wrote:
> Zdenek Kotala <Zdenek(dot)Kotala(at)Sun(dot)COM> writes:
>> I tried to use memory mapped files (mmap) for clog and I think it should be also
>> possible way. I got about 2% better performance, but it needs more testing.
>
> If you only got 2% out of it, it's not even worth thinking about how to
> fix the serious bugs that approach would create (primarily, lack of
> control over when pages can get flushed to disk).
You can flush a pages by msync() function which writes dirty pages on
disk. I don't see any other problem. Originally I tried to fix problem
with a lot of parallel issues reported by Jignesh. However, it needs
more testing if it really helps.
Zdenek
| From | Date | Subject | |
|---|---|---|---|
| Next Message | Tom Lane | 2008-02-06 19:42:18 | Re: Why are we waiting? |
| Previous Message | Robert Treat | 2008-02-06 19:33:15 | Re: crash / data recovery issues |