----- Original Message ----- > From: "Ric Wheeler" <rwheeler@xxxxxxxxxx> > To: "Raghavendra Gowdappa" <rgowdapp@xxxxxxxxxx>, "Saravanakumar Arumugam" <sarumuga@xxxxxxxxxx> > Cc: "Gluster Devel" <gluster-devel@xxxxxxxxxxx>, "Ben Turner" <bturner@xxxxxxxxxx>, "Ben England" > <bengland@xxxxxxxxxx> > Sent: Tuesday, September 27, 2016 10:51:48 AM > Subject: Re: libgfapi zero copy write - application in samba, nfs-ganesha > > On 09/27/2016 07:56 AM, Raghavendra Gowdappa wrote: > > +Manoj, +Ben turner, +Ben England. > > > > @Perf-team, > > > > Do you think the gains are significant enough, so that smb and nfs-ganesha > > team can start thinking about consuming this change? > > > > regards, > > Raghavendra > > This is a large gain but I think that we might see even larger gains (a lot > depends on how we implement copy offload :)). Can you elaborate on what you mean "copy offload"? If it is the way we avoid a copy in gfapi (from application buffer), following is the workflow: <commit> Work flow of zero copy write operation: -------------------------------------- 1) Application requests a buffer of specific size. A new buffer is allocated from iobuf pool, and this buffer is passed on to application. Achieved using "glfs_get_buffer" 2) Application writes into the received buffer, and passes that to libgfapi, and libgfapi in turn passes the same buffer to underlying translators. This avoids a memcpy in glfs write Achieved using "glfs_zero_write" 3) Once the write operation is complete, Application must take the responsibilty of freeing the buffer. Achieved using "glfs_free_buffer" </commit> Do you've any suggestions/improvements on this? I think Shyam mentioned an alternative approach (for zero-copy readv I think), let me look up at that too. regards, Raghavendra > > Worth looking at how we can make use of it. > > thanks! > > Ric > > > > > ----- Original Message ----- > >> From: "Saravanakumar Arumugam" <sarumuga@xxxxxxxxxx> > >> To: "Gluster Devel" <gluster-devel@xxxxxxxxxxx> > >> Sent: Monday, September 26, 2016 7:18:26 PM > >> Subject: libgfapi zero copy write - application in samba, > >> nfs-ganesha > >> > >> Hi, > >> > >> I have carried out "basic" performance measurement with zero copy write > >> APIs. > >> Throughput of zero copy write is 57 MB/sec vs default write 43 MB/sec. > >> ( I have modified Ben England's gfapi_perf_test.c for this. Attached the > >> same > >> for reference ) > >> > >> We would like to hear how samba/ nfs-ganesha who are libgfapi users can > >> make > >> use of this. > >> Please provide your comments. Refer attached results. > >> > >> Zero copy in write patch: http://review.gluster.org/#/c/14784/ > >> > >> Thanks, > >> Saravana > > _______________________________________________ Gluster-devel mailing list Gluster-devel@xxxxxxxxxxx http://www.gluster.org/mailman/listinfo/gluster-devel
