On 09/21/2011 02:50 PM, Benny Halevy wrote: > On 2011-09-21 14:42, Boaz Harrosh wrote: >> On 09/21/2011 02:27 PM, Benny Halevy wrote: >>>> Unless we do following: >>>> 1. preallocate memory for extent state convertion >>>> 2. use nfsiod/rpciod to handle bl_write_cleanup >>>> 3. for pnfs error case, create a kthread to recollapse and resend to MDS >>>> I don't quite understand. How do you use nfs state manager to do other tasks? >>> >>> You need to keep a list of things to do hanging off of the nfs client structure >>> and set a bit in cl_state telling the state manager it has work to do >>> and wake it up. It then needs to go over the list of, say nfs_inodes >>> and call into the layout driver to handle the errors. >>> >>> Benny >> >> Good god, Is it not already too complicated? >> >> The LD is out of the picture. You all seemed to agree that >> the LD has reported an io_done on the nfsiod/rpciod, and in the error case >> Generic layer needs to do it's coalescing on some other thread. So >> your description above is not correct, the LD is out of the picture. >> > > True, if the ld cleanup on io_done is sufficient. > >> It all looks too complicated for me. A pnfs workqueue for both 2 and 3 >> above is very good. Specially since the workqueue also shares global >> pool threads, No? I like it that there is a preallocated thread for >> the error-case, think about it. > > I'm fine too with using a workqueue for the error case. > But I'd rather have the common case done path do only lightweight, > wait free processing. > > Benny > If by "common case done path do only lightweight" you mean "preallocate memory for extent state conversion". Then I absolutely agree. But as far as workqueue/kthread then nfsiod/rpciod-wq or pnfs-wq is exactly the same for the "common case". Unless I'm totally missing the point. What are you saying? These are the options so far: [Toe's option which he rather not] 1. preallocate memory for extent state conversion 2. use nfsiod/rpciod to handle bl_write_cleanup 3. for pnfs error case, create a kthread to recollapse and resend to MDS [My option which I think Toe agrees with] 1. preallocate memory for extent state conversion 2. use pnfs-wq to handle bl_write_cleanup 3. pnfs error case, just like Toe's patches as part of io_done on pnfs-wq Any other options? Boaz -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
