Re^3: Thread local variables in Thread::Pool::Simple

Don't threads use any available CPUs? Maybe not.

Anyway, since Thread::Pool::Simple uses threads, the simplest solution it just to add use forks; early in your program. (Before use Thread::Pool::Simple;, at least.)

By the way, how often do you end up connecting to the database? Maybe the parent should do all the database stuff. ( Why does a parser even need a database? )

I wonder how well profilers deal with threads. ( "Devel::NYTProf is not currently thread safe." doh! )

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Re^4: Thread local variables in Thread::Pool::Simple by Annirak (Novice) on Sep 18, 2009 at 17:19 UTC
The database is connected to once per file. SQLite is supposed to handle multiple connections, but I don't know if buffering is in place or how well it handles multithreading. [Update: The parser is used for profiling files; the results are stored in the database. I'm using an existing framework and, honestly, the database seems to make sense.] I had debated using a queue to bring results back to the parent thread to handle all the requests. This requires a lot more code restructuring, so I didn't follow that approach initially. Right now, with the 60% drop in performance for adding threading, it doesn't seem like it's worthwhile to pursue queuing database insertions. I suppose I could check if it's worthwhile to do db commits in the parent by doing some code profiling, but since I don't have a framework in place for that, I expect it would be more work than just trying the queue. Just to clarify, if I put "use forks" in before "use Thread::Pool::Simple", then I'll get multiprocessing instead of multithreading?	[reply]
Re^5: Thread local variables in Thread::Pool::Simple by ikegami (Patriarch) on Sep 18, 2009 at 17:33 UTC
hmmm, I seem to remember SQLite have some really bad concurrency issues. As in blocking everything in addition to the first connection or transaction or something like that. Obviously, I'm not sure about this.	[reply]