On 09/29/2016 12:41 PM, Wouter Verhelst wrote: > On Thu, Sep 29, 2016 at 10:03:50AM -0400, Josef Bacik wrote: >> So think of it like normal disks with multiple channels. We don't send >> flushes >> down all the hwq's to make sure they are clear, we leave that decision up to >> the >> application (usually a FS of course). > > Well, when I asked earlier, Christoph said[1] that blk-mq assumes that > when a FLUSH is sent over one channel, and the reply comes in, that all > commands which have been received, regardless of which channel they were > received over, have reched disk. > > [1] Message-ID: <[email protected]> > > It is impossible for nbd to make such a guarantee, due to head-of-line > blocking on TCP. >
Huh I missed that. Yeah that's not possible for us for sure, I think my option idea is the less awful way forward if we want to address that limitation. Thanks, Josef ------------------------------------------------------------------------------ _______________________________________________ Nbd-general mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/nbd-general
