Re: Close sometime takes a long time

[Howard Chu <hyc@symas.com>]

Hallvard Breien Furuseth wrote:
> On 05/19/2014 04:05 PM, Venkat Murty wrote:
> > Why does close sometime take a long time?
> >        mdb_env_close  (in sync7320902242508427276.so) + 69  [0x112e37d35]
> >          mdb_env_close0  (in sync7320902242508427276.so) + 248  [0x112e37948]
> >             close  (in libsystem_kernel.dylib) + 10  [0x7fff8bf900c2]
> >
> > Usually, happens when I have killed the process the last time.
> >
> > System: Mac OS X
>
> Do you mean when the last existing process using the enviornment
> is exiting?  If so, that makes sense:
>
> On BSD systems, mdb_env_close() attempts to upgrade the readlock
> on the lockfile to a writelock.  If that succeeds, it deletes
> its semaphores since this is the last process using them.
>
> But if you mean you killed the process, started another and then
> close takes a long time, I don't know why.

It seems he's talking specifically about the close(2) syscall taking a long 
time. Someone would have to peek inside the MacOSX kernel source code to 
answer that question.

--
  -- Howard Chu
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  Director, Highland Sun     http://highlandsun.com/hyc/
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