Re: libgcc double-free, backend won't die
От | James Mansion |
---|---|
Тема | Re: libgcc double-free, backend won't die |
Дата | |
Msg-id | 4765A581.7040801@mansionfamily.plus.com обсуждение исходный текст |
Ответ на | Re: libgcc double-free, backend won't die (Tom Lane <tgl@sss.pgh.pa.us>) |
Ответы |
Re: libgcc double-free, backend won't die
|
Список | pgsql-performance |
Tom Lane wrote: > Yes. > > 1) It's of no value to us > > 2) On many platforms there is a nonzero performance penalty > > I think you have your head in the ground, but its your perogative. *You* might not care, but anyone wanting to use thread-aware libraries (and I'm *not* talking about threading in any Postgres code) will certainly value it if they can do so with some stability. There's a clear benefit to being able to use such code. I suggested a build option but you reject it out of hand. And in doing so, you also lock out the benefits that you *could* have as well, in future.. It seems religious, which is unfortunate. Are you suggesting that the performance penalty, apart from the malloc performance (which is easily dealt with) is *material*? An extra indirection in access to errno will hurt so much? Non-zero I can accept, but clinging to 'non-zero' religiously isn't smart, especially if its a build-time choice. We'll clearly move to multiple cores, and the clock speed enhancements will slow (at best). In many cases, the number of available cores will exceed the number of instantaneously active connections. Don't you want to be able to use all the horsepower? Certainly on the sort of systems I work in my day job (big derivative trading systems) its the norm that the cache hit rate on Sybase is well over 99%, and such systems are typically CPU bound. Parallelism matters, and will matter more and more in future. So, an ability to start incrementally adding parallel operation of some actions (whether scanning or updating indices or pushing data to the peer) is valuable, as is the ability to use threaded libraries - and the (potential?) ability to use embedded languages and more advanced libraries in Postgres procs is one of the advantages of the system itself. (I'd like to discount the use of a runtime in a seperate process - the latency is a problem for row triggers and functions) James
В списке pgsql-performance по дате отправления: