Beefy Boxes and Bandwidth Generously Provided by pair Networks
Problems? Is your data what you think it is?

Re^3: Efficient bit-twiddling in Perl.

by Tux (Abbot)
on Mar 01, 2013 at 07:24 UTC ( #1021171=note: print w/replies, xml ) Need Help??

in reply to Re^2: Efficient bit-twiddling in Perl.
in thread Efficient bit-twiddling in Perl.

I think you can shave off a lot in XS (or Inline::C) when you switch to prebound variables, ala bind_columns () in DBI or Text::CSV_XS, as much of the XS overhead is stack-work. That said, it then is still is function calls, so the stack will be involved. If you pre-bind both in- AND out- parameters, you don't need to push variables on the stack and pop return values of the stack. That should speed up quite a bit.

The next step could be looking in to op-hooks, so there are no real perl-level function calls anymore, but looking at what you already have, I'm wondering if it would be worth the effort (other than to learn from it),

The lookup solutions have array-index ops in the back. I am stunned by the 20% gain you get, and wonder if that would differ per perl version and/or architecture.

Anyway, the solution that is fastest on the machine the problem is solved on is most important, even if another method would be four times faster on z/OS with perl4 :)

Enjoy, Have FUN! H.Merijn

Log In?

What's my password?
Create A New User
Node Status?
node history
Node Type: note [id://1021171]
[choroba]: I'm curious which part of your signature do they find offensive.
[LanX]: they?
[LanX]: click!
[choroba]: they
[LanX]: why do you think it's more than one person?
[Your Mother]: Because we are LEGION! Fix YOUR SIG SIG BLOCK!!!!
[Your Mother]: Forgot to sign in as my sockpuppet, how embarrassing!
[1nickt]: pryrt I am creating a Type to check valid user IDs, which must be a whole number greater than or equal to zero. I would like to disallow 1.0 but because of this behaviour, by the time it is checked by the constraint, it *is* an Int.
[LanX]: should this be considered? Re: Parsing .txt into arrays

How do I use this? | Other CB clients
Other Users?
Others meditating upon the Monastery: (15)
As of 2017-05-24 20:11 GMT
Find Nodes?
    Voting Booth?