Perl slowness

[Noam Rathaus]

Hi Gabor,

I didn't check the network traffic, or name resolving, though both are quite
fast

Both are running v5.10.0 i486-linux-gnu-thread-multi

They are on different networks

I don't think its a "name" collision, I agree the name DB is not a good
choice :)

tcpdump shows no name resolution occuring during the execution - so I don't
think is the issue

The DB package, connects to the mysql via socket, other packages I tried
that are also slow, don't connect to mysql

In any case, MySQL responds within milliseconds to a connection request, so
I don't think this is the issue.

On Tue, Sep 8, 2009 at 4:51 PM, Gabor Szabo <szabgab at gmail.com> wrote:

> 2009/9/8 Noam Rathaus <noamr at beyondsecurity.com>:
> > Hi,
> >
> > I have two machines, their hardware is not identical, but their
> installation
> > is.
> >
> > One is a 3 years old DELL server, while the other is a 1 year old server.
> >
> > One is running 2.6.26-2-686 while the other 2.6.30-1-686
> >
> > What I am seeing is slow startup - emphasis on startup, the code works
> fast
> > once its running - of perl scripts
> >
> > Even the smallest perl script such as this:
> > ===
> > #!/usr/bin/perl
> >
> > use lib '/usr/local/MySystem/lib';
> >
> > use DB;
> >
> > ===
> >
> > Take 7 seconds to start, in comparison to 0.030secods
> >
> > If I don't use the "use DB;" which my package
> >
> > It loads fast
> >
> > I am trying to figure out why, I checked the HD speeds via hdparam, the
> > newer server is 1.5 times faster 103MB/sec
> >
> > I tried to see what libraries were being used, used strace, but I can't
> see
> > something "big" that is causing the delay.
> >
> > The "use DB;" can be replaced with any other "custom" library package I
> > wrote, they all take 2-7 seconds to load, while on the other machine it
> > takes negligible time
> >
> > Does someone have a "thread" to cling to?
>
> DB ?
> Why would you call a package DB, that's the debugger back-end of Perl.
> In any case I would rename those packages to something like
> BeyondSecurity::DB
>
> Are there the same versions of Perl?
> Maybe one of them is actually loading the Perl debugger ?
> Though that should not be slow either.
>
> Have you checked for network activity while you are running the script?
>
> Maybe it is trying to connect somewhere and it is slower (or no
> backward name resolving ?)
>
> Gabor
>
>
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