>> I thought this issue occurs from openssh-3.9 because of introduction of
>> re-exec feature.
>> I tried by disabling the re-exec feature and still I see a large number
>> of
>> close() calls during connection.

> If you run sshd with "-r", how many close() calls do you see per
> connection?
> If it's 60 or so then session.c does this:
> /*
> * Close any extra open file descriptors so that we don't have them
> * hanging around in clients. Note that we want to do this after
> * initgroups, because at least on Solaris 2.3 it leaves file
> * descriptors open.
> */
> for (i = 3; i < 64; i++)
> close(i);
> but I can't see that having a significant performance impact.

Hi Daren,

Actually that was a mistake on my part. When -r option is used the close
call occurs only during startup and not for every connection. During startup
with -r option we get around 60K close calls.
We are about to do a fix for this issue on HP-UX (without -r option). The
approach is to find out the open fds and close the unwanted ones. Will this
be a valid approach.


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