Hi, Boaz, On Wed, Aug 17, 2011 at 4:19 AM, Boaz Harrosh <bharrosh@xxxxxxxxxxx> wrote: > On 08/16/2011 12:20 AM, tao.peng@xxxxxxx wrote: >> >> I tried to rewrite the write patch to handle failures inside >> mds_ops->rpc_release. However, I get a problem w.r.t. "redirty and >> rely on next flush". If the failed write is the *last flush*, we end >> up with relying no one and the dirty pages are simply dropped. Do you >> have any suggestions how to handle it? >> >> Thanks, Tao >> > > Tao Hi. > > OK, I see what you mean. That would be a problem > > I had a totally different idea You know how today we just do: > nfs_initiate_write() > > Which is bad because it can actually dead lock because > we are taking up the only thread that needs to service > that call. Well I thought, with you thread-for-pnfs patch, > can it not now work? I think it is worth a try? The problem w/ directly calling nfs_initiate_write() is that we may have pagelist length larger than server's rsize/wsize. So if client sends all the pages in single READ/WRITE rpc, MDS will reject the READ/WRITE operation. Therefore we need to recoalesce them before re-sending to MDS. > > See if you can advance your thread-for-blocks-objects > patch to current code and inject some errors. I think > it will work this time. What do you think? The thread-for-block-objects patch is to solve the default workqueue deadlock problem. But it can't solve the too large IO size for MDS problem. So I think we need all of the three patches to handle LD IO failures. Thanks, Tao -- 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
