Intermittant slow startup

[Michael Mossey]

Runnng python 2.2 on HP-UX, I get intermittant slow startup.
Sometimes python starts up in a small fraction of a second, and
sometimes takes 3-5 seconds. This applies to any script I run, or
just typing 'python' at the prompt.

I also observed something similar on Linux.

Any ideas what would cause *intermittant* slow startup?

-Mike

 

[Erik Max Francis]

Runnng python 2.2 on HP-UX, I get intermittant slow startup.
Sometimes python starts up in a small fraction of a second, and
sometimes takes 3-5 seconds. This applies to any script I run, or
just typing 'python' at the prompt.

I also observed something similar on Linux.

Any ideas what would cause *intermittant* slow startup?

Caching? Is it a long time between invocations that it takes a long
time to start up?

 

[Michael Mossey]

Caching? Is it a long time between invocations that it takes a long
time to start up?

It is quite intermittant without much of a pattern I can see. One
thing that is definitely true is that if I start up python several
times in a row one right after the other, some can be slow and some
fast. I just observed it start fast twice, then start slow. I don't
remember if it ever does the other way around but I think it does.

-Mike

 

[simo]

I've noticed that on Windows a lot, but not on Linux or Solaris.

 

[Andrew MacIntyre]

It is quite intermittant without much of a pattern I can see. One
thing that is definitely true is that if I start up python several
times in a row one right after the other, some can be slow and some
fast. I just observed it start fast twice, then start slow. I don't
remember if it ever does the other way around but I think it does.

is any resource coming from an NFS mount? or other network source?

 

[Michael Mossey]

is any resource coming from an NFS mount? or other network source?

I double-checked that and asked the sysadmin to check if the python
build was using any network source. I do have AFS and NFS drives
mounted on this machine, but I'm not reading any python code from them
as nearly as I can tell. PYTHONPATH points only to local disk.

-Mike

 

[Andrew MacIntyre]

I double-checked that and asked the sysadmin to check if the python
build was using any network source. I do have AFS and NFS drives
mounted on this machine, but I'm not reading any python code from them
as nearly as I can tell. PYTHONPATH points only to local disk.

All I can think of is to try using "python -v" and see where in the
startup process the delay appears to be occurring. If the same module is
involved in every stumble, then at least you have a module to investigate.

 

[Michael Hudson]

It is quite intermittant without much of a pattern I can see. One
thing that is definitely true is that if I start up python several
times in a row one right after the other, some can be slow and some
fast. I just observed it start fast twice, then start slow. I don't
remember if it ever does the other way around but I think it does.

Does HP-UX have a version of strace/truss/ktrace?

Cheers,
mwh

 

[Michael Mossey]

Does HP-UX have a version of strace/truss/ktrace?

Cheers,
mwh

Yes, it has strace. What do I do with that?

-Mike

 

[Michael Mossey]

All I can think of is to try using "python -v" and see where in the
startup process the delay appears to be occurring. If the same module is
involved in every stumble, then at least you have a module to investigate.

python -v reveals that the hang is coming before it prints anything. So
what is python doing then? Or is the OS having a problem in loading the
python executable and getting it going? This doesn't seem to happen with
other utilities installed in /usr/local/bin.

-Mike

 

[Michael Mossey]

Yes, it has strace. What do I do with that?

-Mike

Okay, the thousands of people who have dropped everything to work on
this for me, you can go back to what you were doing. My shared
library load path included an AFS directory that wasn't necessary.
When I took that out, it worked fine.

Thanks everyone,
Mike