-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Derrick J Brashear wrote: > On Mon, 24 Sep 2007, Adam Megacz wrote: > >> >> "Derrick Brashear" <[EMAIL PROTECTED]> writes: >>> it would involve a semantic change but we could start flushing >>> changes in >>> the background before fsync. there are of course potential issues. >> >> Wouldn't it be the same semantics as if the client cache were rather >> small? > > largely. but this forces the change for everyone. > >> I can get the app to fsync(), though, so it looks like I'll go with that. > > good.
Hi, I looked at this a long time ago, and IIRC the "cache full" behavior was a synchronous one. I.E. cache data was pushed to the server during the write calls, and only enough data was written so that the write in question could succeed. Ideally this activity would occur as a background task starting when the cache hit some high watermark of dirty data, and run until some low watermark had been reached. There is a thread in the cachemanager which handles asynchronous writes when the cachemanager is configured to write after close(I don't remember the option offhand) One of the issues with operating in that mode is that you can have the write fail after the file is closed if for example your tokens expire before all of the dirty data is flushed, but I don't think that would be an issue if you did the background writes while the file was still open, and required everything to be written before the close succeeded. I'm inclined to agree with Adam. I'm not sure this is really a change of semantics for the client. The client does not guarantee that changes will not be sent to the server until a close() or fsync() is called, but rather only that those calls will guarantee that all previously written data is sent to the server. Implementing this is one of the things that's been sitting on my rainy day list for several years now, but somehow there don't seem to be as many rainy days here in California as I used to get back in Pittsburgh ;-) Adam, if you're interested in working on this, feel free to send me an e-mail off list, and we can talk about it more. - -Matt > _______________________________________________ > OpenAFS-info mailing list > [email protected] > https://lists.openafs.org/mailman/listinfo/openafs-info > > -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.7 (GNU/Linux) Comment: Using GnuPG with Fedora - http://enigmail.mozdev.org iD8DBQFHMKH3pLF3UzlwZVgRAlhTAJ0dHA+HEU/gTmWoNOLUEhrlAXJE/gCeKREF bn+v2Kpuj6ZjcKSkw/1q8Ps= =C6sT -----END PGP SIGNATURE----- _______________________________________________ OpenAFS-info mailing list [email protected] https://lists.openafs.org/mailman/listinfo/openafs-info
