Re: thread-safe mmap module ?

in reply to thread-safe mmap module ?

Never used them myself, but a CPAN search for shared cache brings up a number of promising looking modules, including IPC::SharedCache and Cache::FastMmap. The documentation from Cache::FastMmap says:

It uses fcntl locking to ensure multiple processes can safely access the cache at the same time.

so it should certainly be thread-safe.

Comment on Re: thread-safe mmap module ?

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Re^2: thread-safe mmap module ? by perrin (Chancellor) on Feb 22, 2009 at 00:51 UTC
I don't recommend using IPC::SharedCache. It's slow, and the author himself (samtregar) suggest using something else these days, as you can see in the reviews.	[reply]
Re^2: thread-safe mmap module ? by jdd (Acolyte) on Feb 21, 2009 at 22:35 UTC
There is a concern with the win32 support and Cache::FastMmap warns: Cache::FastMmap ./.. will not work on Windows or Win32 like environments. and a google search on IPC::SharedCache says something similar ! Unfortunate, I guess I can fall back to a Tie::Cache or a DB backend module for win32 -; Thanks for your answer btw!	[reply]
Re^3: thread-safe mmap module ? by kennethk (Abbot) on Feb 21, 2009 at 22:49 UTC
Another result that came up on that page is Cache::FastMmap::WithWin32, which "is a fork of Cache::FastMmap by Rob Mueller to include the Win32 port by Ash Berlin". Once again, never used them, but maybe this would fit your bill?	[reply]
Re^4: thread-safe mmap module ? by jdd (Acolyte) on Feb 21, 2009 at 22:55 UTC
You are hitting exactly the reason why I opened this node (smiles) - If I put Cache::FastMmap::WithWin32 in the apache startup.pl I'll hit this piece of code from the module: sub CLONE { die "Cache::FastMmap::WithWin32 does not support threads sorry"; } Damned I said ! Can't find a win32 thread-safe mmap alternative since then.	[reply]
Re^5: thread-safe mmap module ? by kennethk (Abbot) on Feb 21, 2009 at 23:06 UTC
Re^6: thread-safe mmap module ? by jdd (Acolyte) on Feb 21, 2009 at 23:24 UTC
Re^2: thread-safe mmap module ? by zwon (Abbot) on Feb 22, 2009 at 12:14 UTC
It uses fcntl locking to ensure multiple processes can safely access the cache at the same time. so it should certainly be thread-safe. I'm sorry but why? Aren't fcntl locks shared between threads?	[reply]

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