Re: pglz compression performance, take two

On 2/5/23 19:36, Andrey Borodin wrote:
> On Fri, Jan 6, 2023 at 10:02 PM Andrey Borodin <amborodin86@gmail.com> wrote:
>>
>> Hello! Please find attached v8.
> 
> I got some interesting feedback from some patch users.
> There was an oversight that frequently yielded results that are 1,2 or
> 3 bytes longer than expected.
> Looking closer I found that the correctness of the last 3-byte tail is
> checked in two places. PFA fix for this. Previously compressed data
> was correct, however in some cases few bytes longer than the result of
> current pglz implementation.
> 

Thanks. What were the consequences of the issue? Lower compression
ratio, or did we then fail to decompress the data (or would current pglz
implementation fail to decompress it)?


regards

-- 
Tomas Vondra
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