Re: pglz performance

On Fri, Aug 02, 2019 at 11:20:03AM -0700, Andres Freund wrote:
>Hi,
>
>On 2019-08-02 19:52:39 +0200, Tomas Vondra wrote:
>> Hmmm, I don't remember the details of those patches so I didn't realize
>> it allows incremental recompression. If that's possible, that would mean
>> existing systems can start using it. Which is good.
>
>That depends on what do you mean by "incremental"? A single toasted
>datum can only have one compression type, because we only update them
>all in one anyway. But different datums can be compressed differently.
>

I meant different toast values using different compression algorithm,
sorry for the confusion.

>
>> Another question is whether we'd actually want to include the code in
>> core directly, or use system libraries (and if some packagers might
>> decide to disable that, for whatever reason).
>
>I'd personally say we should have an included version, and a
>--with-system-... flag that uses the system one.
>

OK. I'd say to require a system library, but that's a minor detail.

regards

--
Tomas Vondra http://www.2ndQuadrant.com
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