Re: 500 tpsQL + WAL log implementation - Mailing list pgsql-hackers

From Peter Galbavy
Subject Re: 500 tpsQL + WAL log implementation
Date
Msg-id 014101c321e2$dec5b410$24e0a8c0@HATMADDER
Whole thread Raw
In response to Re: 500 tpsQL + WAL log implementation  (Bruce Momjian <pgman@candle.pha.pa.us>)
List pgsql-hackers
Bruce Momjian wrote:
> the idea is to have multiple versions of the last WAL block, meaning
> you
> write the first record of the last block, then when you want to write
> another, your disk platter has moved, so you write the first and
> second records in a new location.

But how much of this is entirely dependent on deterministic prediction of
the disk activity ?

Not only noting the way modern disks have their own write caches (most IDE
drives now come with between 2 and 8 MB), but transparent bad sector
remapping and also filesystem issues with ufs, ext2 and journalling
extensions to both.

While I believe that there is value is working towards a better coupling
between PosetgreSQL and the underlying hardware, is this approach going to
be productive in the "real" world ? Enough to spend time on it ?

Your choice mind, I am just whining.

Peter



pgsql-hackers by date:

Previous
From: Tom Lane
Date:
Subject: Re: vacuum analyze corrupts database
Next
From: "Andrew Dunstan"
Date:
Subject: Re: Plan B for log rotation support: borrow Apache code