Beefy Boxes and Bandwidth Generously Provided by pair Networks
Perl: the Markov chain saw

Re^8: Use more threads.

by BrowserUk (Pope)
on Apr 30, 2013 at 11:27 UTC ( #1031391=note: print w/replies, xml ) Need Help??

in reply to Re^7: Use more threads.
in thread Use more threads.

Simple. Don't load everything into every thread.

  1. Tk isn't threadsafe so it has no business being loaded by more than 1 thread -- preferably the main thread -- so don't use it at the top of the code, require your TK::* modules after you've created your pool of threads.
  2. Likewise, it doesn't make much sense to have DBI/DBD modules in multiple threads. The DB server will serialise the accesses from the multiple threads anyway, with the result that queries and stores will be conflicting within the server and slowing each other down. So serialise it at your end. Start a dedicated DBI thread and queue your accesses to it.

Those two steps alone cut the load time by half on my machine:

C:\test>junk rem As your posted it. Took 4.529284 seconds C:\test>junk rem Tk required after threads started. Took 3.111319 seconds C:\test>junk rem DBI/DBD moved to separate thread. Took 2.166010 seconds

And that is (probably) only the tip of the iceberg. With proper sight of your real code, there are probably lots more simple steps that could be done to improve things no end.

With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'
Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.

Log In?

What's my password?
Create A New User
Node Status?
node history
Node Type: note [id://1031391]
[ambrus]: (b) a good presentation system that lets the presenter quickly interactively edit the slides live during a presentation, to combine the advantages of blackboard and overhead slide styles in modern tech
[Corion]: Heh - in university, I cheated on (a) by doing blackboard presentations using chalk. But those were 2 hour presentations, not quick/essential/ reduced presentations where you want to show something quick
[ambrus]: (either on just one screen or two screens). this is necessary because
[ambrus]: overhead slide plus blackboard is inconvenient because the lighting conditions are different and they require separate areas you can't quickly repartition, and typing on keyboard is faster and more convenient than writing on a blackboard
[Corion]: (b) would be cool. I've thought about this doing Pod editing, and even simply regenerating/live updating the browser makes things much more interactive
[ambrus]: modern computers have way enough processing power to allow this, at least for geeks who are willing to spend a few weeks to learn a tricky new user interface like vim
[Corion]: ambrus: Well, for mathematical notation, I find blackboard much more convenient than a computer. But when inserting text or moving text around, the computer wins obviously
[ambrus]: But either of these is a big problem in practice, so I'd need to spend like thirty years of my life to solve (a) and five more years to solve (b)
[ambrus]: Corion: yes, CURRENTLY the blackboard is more convenient
[ambrus]: and it's not like I want to ban blackboards anyway

How do I use this? | Other CB clients
Other Users?
Others wandering the Monastery: (10)
As of 2017-09-26 10:21 GMT
Find Nodes?
    Voting Booth?
    During the recent solar eclipse, I:

    Results (293 votes). Check out past polls.