linux performance puzzle

Hi all,

I have a program that reads 100000 lines from stdin, performs
processing in two worker threads (there are two processors on my
system), and outputs the result into a file. To make the test
cleaner, I excluded all file operations by reading from a pipe
(created by another small program I wrote), and redirecting the output
into /dev/null.

Now the puzzle: while it generally takes about 11.5 sec to execute my
test, the first run after rebuild takes _significantly_ more,
sometimes 19 sec, sometimes 15, etc. All the subsequent runs
consistently take around 11.5 sec.

I noted that I actually need to rebuild -- just touching the
executable does not have the same effect.

I am not using any shared objects that need to be downloaded over the
network.

My system is:
Red Hat Enterprise Linux WS release 4 (Nahant Update 2)

Can anybody suggest any explanation of this?

Thanks in advance,
Arkadiy
.

Relevant Pages

  • Re: linux performance puzzle
    ... processing in two worker threads (there are two processors on my ... I excluded all file operations by reading from a pipe ... All the subsequent runs ... in the cold-cache startup penalty after rebuild. ...
    (comp.unix.programmer)
  • Re: alter index (Oracle Text index) rebuild on different schema => no rights
    ... I put the "alter index" statement in a stored procedure and put it in ... The execution of the package has to ... Execute it dynamically as a workaround. ... REBUILD statement without proper PARAMETERS clause (which ...
    (comp.databases.oracle.misc)
  • Re: Write Access Error When Using CFileDialog
    ... error only occurs when I push my 'browse' button and execute the code ... in which case the compiler gives you an undefined symbol error. ... Perhaps you would be effectively served if you deleted the button from the toolbar. ... and rebuild it, and when I rebuild it, it tells me this: ...
    (microsoft.public.vc.mfc)
  • Re: makefile adding dependencies
    ... If I read this right it will execute the depend then rebuild it's self ... When GNU make (I don't know if this works for any other flavours of ...
    (comp.unix.programmer)
  • Re: Changing Default Views
    ... Enquire, plan and execute ... view during File operations so I can see more content before having ... Folder Options | View | Apply to All Folders does not live up to its ...
    (microsoft.public.windowsxp.help_and_support)
Loading