On Fri, 2017-06-23 at 10:56 -0400, J. Bruce Fields wrote: > On Tue, Jun 20, 2017 at 07:35:35PM -0400, Trond Myklebust wrote: > > The following patches are intended to smooth out the page writeback > > performance by ensuring that we commit the data earlier on the > > server. > > Was there some particular benchmark or hardware setup that motivated > doing this now? I finally had enough free time to study the problem of why my backups from my laptop to my NAS backup device took so long to complete, and why the 'rsync' bandwidth display is so inconsistent. > > --b. > > > > > We assume that if something is starting writeback on the pages, > > then > > that process wants to commit the data as soon as possible, whether > > it > > is an application or just the background flush process. > > We also assume that for streaming type processes, we don't want to > > pause > > the I/O in order to commit, so we don't want to rely on a counter > > of > > in-flight I/O to the entire inode going to zero. > > > > We therefore set up a monitor that counts the number of in-flight > > writes for each call to nfs_writepages(). Once all the writes to > > that > > call to nfs_writepages has completed, we send the commit. Note that > > this > > mirrors the behaviour for O_DIRECT writes, where we similarly track > > the > > in-flight writes on a per-call basis. > > > > Trond Myklebust (3): > > NFS: Remove unused fields in the page I/O structures > > NFS: Ensure we commit after writeback is complete > > NFS: Fix commit policy for non-blocking calls to > > nfs_write_inode() > > > > fs/nfs/pagelist.c | 5 ++-- > > fs/nfs/write.c | 59 > > +++++++++++++++++++++++++++++++++++++++++++++++- > > include/linux/nfs_page.h | 2 +- > > include/linux/nfs_xdr.h | 3 ++- > > 4 files changed, 64 insertions(+), 5 deletions(-) > > > > -- > > 2.9.4 > > > > -- > > 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 > > -- Trond Myklebust Linux NFS client maintainer, PrimaryData trond.myklebust@xxxxxxxxxxxxxxx ��.n��������+%������w��{.n�����{��w��� jg��� �����ݢj����G���� ���j:+v���w�m������w�������h�����٥
