Hao,
Usually I hit the protocol deadlocks whenever I made any changes in the
coherence protocols. The sequencer in Ruby periodically scans the status of
inflight read/write reqs in MSHR tables and if any req does not get service
after a certain time, it flags the protocol deadlock warning and aborts the
program. Since the program aborts, so it is easy to trace back to the request
that hasn't got service and find whatsoever reasons behind that using the
debug-flags i mentioned. I do not know, making changes in # MCs will work or
not as I havn't hit any deadlock due to the MCs!
Dibakar
On 08/10/12, Hao Wang
wrote:
> Hey Dibakar,
>
> So you mean this must be the problem of the mechanism of my memory system?
>
>
> I also have this problem for certain benchmark with more cpu cores. (16 cores
> with 4 MCs, while 4 cores with 2 MCs works).
> But I've modified my scheduling policy of memory controller as FIFO, the
> problem still happens, which I think does not make sense.
>
>
> Hao
>
> On Fri, Aug 10, 2012 at 12:03 AM, Dibakar Gope <gem5-users@gem5.org
> <g...@wisc.edu')" target="1">g...@wisc.edu> wrote:
>
> > Turn on the ProtocolTrace, RubyGenerated, RubySlicc debug-flags and begin
> > tracing at few cycles before the deadlock occurs (3352000000000 should be
> > fine for ur case). You will get a clear idea of why the read request could
> > not manage to get service from the memory system
> >
> > -Dibakar
> >
> > On 08/09/12, jinsong wrote:
> > >
> > > BLOCKQUOTE { MARGIN-TOP: 0px; MARGIN-BOTTOM: 0px; MARGIN-LEFT: 2em } OL {
> > > MARGIN-TOP: 0px; MARGIN-BOTTOM: 0px } UL { MARGIN-TOP: 0px;
> > > MARGIN-BOTTOM: 0px } P { MARGIN-TOP: 0px; MARGIN-BOTTOM: 0px } BODY {
> > > LINE-HEIGHT: 1.5; FONT-FAMILY: 微软雅黑; COLOR: #000000; FONT-SIZE: 10.5pt }
> > >
> > > Hi All,
> > > I am running PARSEC on gem5 in ALPHA FS mode. With the following
> > > commands, a deadlock problem occurred:
> > > ###gem5 command line options###
> > > ~/gem5/build/ALPHA_MOESI_hammer/gem5.opt configs/example/ruby_fs.py
> > > --cpu-type=timing -n 16 --clock='1GHz' --l1i_size=32kB
> > > --l1d_size=32kB --l2_size=16MB --num-l2caches=16 --num-dirs=16
> > > --cacheline_size=64 --caches --ruby --topology=Mesh
> > > --garnet-network=fixed --mesh-rows=4 --kernel=vmlinux_2.6.27-gcc_4.3.4
> > > --script=~/gem5/configs/boot/blackscholes-ckpts.rcS
> > >
> > > ###below is the running results:###
> > > ...
> > > warn: Prefetch instructions in Alpha do not do anything
> > > warn: Prefetch instructions in Alpha do not do anything
> > > warn: Prefetch instructions in Alpha do not do anything
> > > hack: be nice to actually delete the event here
> > > info: Entering event queue @ 3352057344000. Starting simulation...
> > > Writing checkpoint
> > > info: Entering event queue @ 3352057347000. Starting simulation...
> > > info: Entering event queue @ 3352057347000. Starting simulation...
> > > panic: Possible Deadlock detected. Aborting!
> > > version: 0 request.paddr: 0x[0x6d48, line 0x6d40] m_readRequestTable: 1
> > > current time: 3352557347 issue_time: 3352057347 difference: 500000
> > > @ cycle 3352557347000
> > > [wakeup:build/ALPHA_MOESI_hammer/mem/ruby/system/Sequencer.cc, line 108]
> > > Memory Usage: 1325856 KBytes
> > > Program aborted at cycle 3352557347000
> > > Aborted
> > >
> > >
> > > So how should I fix this problem? Any help greatly appreciated!
> > >
> > > Best regards,
> > > Song Jin
> > >
> > > ------------------------------------------------------------------------
> > > Song Jin, Ph. D.
> > > Department of Electronic and Communication Engineering
> > > School of Electrical and Electronic Engineering
> > > North China Electric Power University, P. R. China
> > > Web: http://www.ncepu.edu.cn
> > > ------------------------------------------------------------------------
> >
> >
> > _______________________________________________
> > gem5-users mailing list
> > http://m5sim.org/cgi-bin/mailman/listinfo/gem5-users(javascript:main.compose('new',
> > 't=gem5-users@gem5.org>
> >
> >
> > --
> > ------------------------------------------------------ Wang, Hao
> > http://homepages.cae.wisc.edu/~wangh/
> >
> >
> > Ph.D. candidate
> > Dept. of Electrical & Computer Engineering
> > University of Wisconsin, Madison
> >
> > B.S. from
> > Department of Microelectronics
> > School of Electronics Engineering and Computer Science
> > Peking University
_______________________________________________
gem5-users mailing list
gem5-users@gem5.org
http://m5sim.org/cgi-bin/mailman/listinfo/gem5-users
