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Re: Mutex optimization for uncontested cases
- To: Luoqi Chen <lchen at onetta dot com>
- Subject: Re: [ECOS] Mutex optimization for uncontested cases
- From: Jonathan Larmour <jlarmour at redhat dot com>
- Date: Tue, 25 Sep 2001 20:45:02 +0100
- Cc: ecos-discuss at sources dot redhat dot com
- Organization: Red Hat UK Ltd.
- References: <200109250140.f8P1eOd21018@photon.onetta.com>
Luoqi Chen wrote:
>
> I have noticed very poor performance of stdio stream under eCos, about 4 times
> slower than vxworks. Howerver I was able to improve the performance by a factor
> of 2 by disabling the CYGSEM_LIBC_STDIO_THREAD_SAFE_STREAMS option. This points
> to an inefficiency in the current mutex implementation that we do not optimize
> for the most common cases of uncontested mutex acquisitions. I wonder if eCos
> developers are aware of this problem and if there is any effort under way
> trying to resolve it.
That's not a priority for us right now. It's open source, so patches
welcome! Bear in mind that atomic test and set type operations aren't
portable :-|.
Jifl
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