Re: Enabling Checksums
От | Jeff Davis |
---|---|
Тема | Re: Enabling Checksums |
Дата | |
Msg-id | 1366658541.2646.50.camel@sussancws0025 обсуждение исходный текст |
Ответ на | Re: Enabling Checksums (Ants Aasma <ants@cybertec.at>) |
Список | pgsql-hackers |
On Mon, 2013-04-22 at 19:25 +0300, Ants Aasma wrote: > I was just now writing up a generic C based patch based on the > parallel FNV-1a + shift that we discussed with Florian with an added > round of mixing. Testing the performance in isolation indicates that: > 1) it is about an order of magnitude faster than the Sarwate CRC > method used in Postgresql. > 2) it is about 2x faster than fastest software based CRC method. > 3) by using -msse4.1 -funroll-loops -ftree-vectorize compilation > options the performance improves 5x. (within 20% of handcoded ASM) That's great news! This means that we can have a simple C implementation in a separate file, and pass a few build flags when compiling just that file (so it doesn't affect other code). That should make reviewers/committers happy (including me). FWIW, that was my last real concern about FNV (reviewability). I'm not worried about the performance based on your analysis; nor am I worried about the error detection rate. Regards,Jeff Davis
В списке pgsql-hackers по дате отправления: