Re: VM question related to faults

mykola.stryebkov@xxxxxxxxx wrote:

On 31.07.2006 14:12:20, Intron wrote:

Mutex(9) is sometimes too heavy, and has many limitations, while sx(9)
is somewhat enough.

First paragraph from sx(9) manual says:

Shared/exclusive locks are used to protect data that are read
far more often than they are written. Mutexes are inherently
more efficient than shared/exclusive locks, so shared/exclusive
locks should be used prudently.


--
Nick Strebkov
Public key: http://humgat.org/~nick/pubkey.txt
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But sx(9) also says in section "CONTEXT",

A thread may hold a shared or exclusive lock on an sx lock while sleep-
ing.

You may try copyout() when holding a mutex(9) on 7.0-CURRENT.
Look out for kernel crash.

------------------------------------------------------------------------
From Beijing, China

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