Re: Are there plans to add data compression feature to postgresql? - Mailing list pgsql-general

From Tom Lane
Subject Re: Are there plans to add data compression feature to postgresql?
Date
Msg-id 28357.1225406511@sss.pgh.pa.us
Whole thread Raw
In response to Re: Are there plans to add data compression feature to postgresql?  ("Scott Marlowe" <scott.marlowe@gmail.com>)
Responses Re: Are there plans to add data compression feature to postgresql?  ("Scott Marlowe" <scott.marlowe@gmail.com>)
List pgsql-general
"Scott Marlowe" <scott.marlowe@gmail.com> writes:
> On Thu, Oct 30, 2008 at 4:01 PM, Gregory Stark <stark@enterprisedb.com> wrote:
>> I can't really see trusting Postgres on a filesystem that felt free to
>> compress portions of it. Would the filesystem still be able to guarantee that
>> torn pages won't "tear" across adjacent blocks? What about torn pages that
>> included hint bits being set?

> I can't see PostgreSQL noticing it. PostgreSQL hands the OS a 512byte
> block, the OS compresses it and it's brethren as the go to disk,
> uncompresses as they come out, and as long as what you put in is what
> you get back it shouldn't really matter.

I think Greg's issue is exactly about what guarantees you'll have left
after the data that comes back fails to be the data that went in.

            regards, tom lane

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