Re: flock or IPC semaphore for atomic appends

From: A. Sinan Unur (asu1_at_c-o-r-n-e-l-l.edu)
Date: 11/14/03 

Date: 14 Nov 2003 15:22:13 GMT

adwser@hotmail.com (jtd) wrote in
news:c57c103.0311140015.7052583b@posting.google.com:

> 2) Why is flock processor intensive? Does flock write something to
> disk when locking/unlocking?

>From perldoc -f flock:

Two potentially non-obvious but traditional "flock" semantics
are that it waits indefinitely until the lock is granted, and
that its locks merely advisory.

I haven't looked at the source, but I think it is this waiting indefinitely
part (polling?) that's causing CPU usage to go up.

Sinan. 

-- 
A. Sinan Unur
asu1@c-o-r-n-e-l-l.edu
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