Re: [gem5-dev] Review Request 3809: imported patch rr_arbiter_fix
--- This is an automatically generated e-mail. To reply, visit: http://reviews.gem5.org/r/3809/#review9426 --- Ship it! Ship It! - Jason Lowe-Power On Feb. 12, 2017, 4:36 a.m., Tushar Krishna wrote: > > --- > This is an automatically generated e-mail. To reply, visit: > http://reviews.gem5.org/r/3809/ > --- > > (Updated Feb. 12, 2017, 4:36 a.m.) > > > Review request for Default, Brad Beckmann, Jieming Yin, Matthew Poremba, and > Onur Kayiran. > > > Repository: gem5 > > > Description > --- > > ruby: fix round robin arbiter in garnet2.0 > The rr arbiter pointer in garnet was getting updated on every request, > even if there is no grant. This was leading to a huge variance in wait > time at a router at high injection rates. > This patch corrects it to update upon a grant. > > > Diffs > - > > src/mem/ruby/network/garnet2.0/SwitchAllocator.cc 79c3f6a60392 > > Diff: http://reviews.gem5.org/r/3809/diff/ > > > Testing > --- > > > Thanks, > > Tushar Krishna > > ___ gem5-dev mailing list gem5-dev@gem5.org http://m5sim.org/mailman/listinfo/gem5-dev
Re: [gem5-dev] Review Request 3809: imported patch rr_arbiter_fix
> On Feb. 12, 2017, 4:50 a.m., Jieming Yin wrote: > > We also observed long packet delay in heavy-traffic workloads. Just > > curious, how much does this fix improve? I noticed the problem when the deadlock threshold that was added recently started getting triggered at very high injection rates (post-saturation) with the synthetic network traffic. It seemed odd to me that a NI could not inject for 1 cycles, however congested the network may be, as round-robin should ensure that eventually every VC at every input port should get a chance to leave the router (in the absence of a true deadlock). I didn't measure how the overall stats change now, but the deadlock counter does not trigger now even if I (try to) inject 1-flit every cycle showing that this fix works. - Tushar --- This is an automatically generated e-mail. To reply, visit: http://reviews.gem5.org/r/3809/#review9418 --- On Feb. 12, 2017, 4:36 a.m., Tushar Krishna wrote: > > --- > This is an automatically generated e-mail. To reply, visit: > http://reviews.gem5.org/r/3809/ > --- > > (Updated Feb. 12, 2017, 4:36 a.m.) > > > Review request for Default, Brad Beckmann, Jieming Yin, Matthew Poremba, and > Onur Kayiran. > > > Repository: gem5 > > > Description > --- > > ruby: fix round robin arbiter in garnet2.0 > The rr arbiter pointer in garnet was getting updated on every request, > even if there is no grant. This was leading to a huge variance in wait > time at a router at high injection rates. > This patch corrects it to update upon a grant. > > > Diffs > - > > src/mem/ruby/network/garnet2.0/SwitchAllocator.cc 79c3f6a60392 > > Diff: http://reviews.gem5.org/r/3809/diff/ > > > Testing > --- > > > Thanks, > > Tushar Krishna > > ___ gem5-dev mailing list gem5-dev@gem5.org http://m5sim.org/mailman/listinfo/gem5-dev
[gem5-dev] Review Request 3809: imported patch rr_arbiter_fix
--- This is an automatically generated e-mail. To reply, visit: http://reviews.gem5.org/r/3809/ --- Review request for Default, Brad Beckmann, Jieming Yin, Matthew Poremba, and Onur Kayiran. Repository: gem5 Description --- ruby: fix round robin arbiter in garnet2.0 The rr arbiter pointer in garnet was getting updated on every request, even if there is no grant. This was leading to a huge variance in wait time at a router at high injection rates. This patch corrects it to update upon a grant. Diffs - src/mem/ruby/network/garnet2.0/SwitchAllocator.cc 79c3f6a60392 Diff: http://reviews.gem5.org/r/3809/diff/ Testing --- Thanks, Tushar Krishna ___ gem5-dev mailing list gem5-dev@gem5.org http://m5sim.org/mailman/listinfo/gem5-dev
