> -----Original Message----- > From: Tom Tucker [mailto:t...@opengridcomputing.com] > Sent: Saturday, February 27, 2010 8:23 PM > To: Vu Pham > Cc: Roland Dreier; linux-r...@vger.kernel.org; Mahesh Siddheshwar; > ewg@lists.openfabrics.org > Subject: Re: [ewg] nfsrdma fails to write big file, > > Roland Dreier wrote: > > > + /* > > > + * Add room for frmr register and invalidate WRs > > > + * Requests sometimes have two chunks, each chunk > > > + * requires to have different frmr. The safest > > > + * WRs required are max_send_wr * 6; however, we > > > + * get send completions and poll fast enough, it > > > + * is pretty safe to have max_send_wr * 4. > > > + */ > > > + ep->rep_attr.cap.max_send_wr *= 4; > > > > Seems like a bad design if there is a possibility of work queue > > overflow; if you're counting on events occurring in a particular > order > > or completions being handled "fast enough", then your design is going > to > > fail in some high load situations, which I don't think you want. > > > > > > Vu, > > Would you please try the following: > > - Set the multiplier to 5 > - Set the number of buffer credits small as follows "echo 4 > > /proc/sys/sunrpc/rdma_slot_table_entries" > - Rerun your test and see if you can reproduce the problem? > > I did the above and was unable to reproduce, but I would like to see if > you can to convince ourselves that 5 is the right number. > >
Tom, I did the above and can not reproduce either. I think 5 is the right number; however, we should optimize it later. -vu _______________________________________________ ewg mailing list ewg@lists.openfabrics.org http://lists.openfabrics.org/cgi-bin/mailman/listinfo/ewg