On Tue, Jul 7, 2015 at 10:31 PM, Joshua D. Drake <j...@commandprompt.com> wrote:
> > On 07/07/2015 08:05 PM, Craig James wrote: > >> >> >> No ideas, but I ran into the same thing. I have a set of C/C++ functions >> that put some chemistry calculations into Postgres as extensions (things >> like, "calculate the molecular weight of this molecule"). As SQL >> functions, the whole thing bogged down, and we never got the scalability >> we needed. On our 8-CPU setup, we couldn't get more than 2 CPUs busy at >> the same time, even with dozens of clients. >> >> When I moved these same functions into an Apache fast-CGI HTTP service >> (exact same code, same network overhead), I could easily scale up and >> use the full 100% of all eight CPUs. >> >> I have no idea why, and never investigated further. The convenience of >> having the functions in SQL wasn't that important. >> > > I admit that I haven't read this whole thread but: > > Using Apache Fast-CGI, you are going to fork a process for each instance > of the function being executed and that in turn will use all CPUs up to the > max available resource. > > With PostgreSQL, that isn't going to happen unless you are running (at > least) 8 functions across 8 connections. Well, right, which is why I mentioned "even with dozens of clients." Shouldn't that scale to at least all of the CPUs in use if the function is CPU intensive (which it is)? Craig > > JD > > -- > Command Prompt, Inc. - http://www.commandprompt.com/ 503-667-4564 > PostgreSQL Centered full stack support, consulting and development. > Announcing "I'm offended" is basically telling the world you can't > control your own emotions, so everyone else should do it for you. > -- --------------------------------- Craig A. James Chief Technology Officer eMolecules, Inc. ---------------------------------
