portelli/Grid
1
0 Fork 0
mirror of https://github.com/paboyle/Grid.git synced 2026-10-20 14:23:17 +01:00
Code Releases Activity

SUMMA telemetry: ring time histogram by message size

Browse Source 
Per log2-size bucket: messages, GB, seconds inside SendToRecvFrom, GB/s,
% of ring time.  Decomposes the 2 GB/s/rank average (probe: 11-20 GB/s
at 8 MB) into latency-bound small messages vs slow large ones vs wait.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01RAhdQHrkzKmzfxpxW1whLn
This commit is contained in:
Peter BoyleandClaude Fable 5 committed 2026-08-27 02:02:30 -04:00
1 parent 96071aa492
commit 0979371c45
2 files changed
+31 -1
Download Patch File Download Diff File Expand all files Collapse all files

No files matched your search

Grid/algorithms/multigrid/BlockCyclicSchurInverse.h
+19
View File
@@ -397,6 +397,25 @@ public:
<< " gemm min/max " << gmin << "/" << gmax
<< " | ring bytes/rank " << gb << " GB -> " << (ring>0 ? gb/ring : 0.0) << " GB/s/rank (boss)"
<< std::endl;
// Ring time decomposed by message size (boss rank; every rank sends the
// same sequence of sizes). Time is wall time inside SendToRecvFrom, so it
// includes waiting for the partner -- a bucket whose GB/s is far below the
// probe's for the same size is wait, not wire.
std::cout << GridLogMessage << "BlockCyclicSumma ring histogram (boss): size-bucket msgs GB secs GB/s %time" << std::endl;
std::streamsize oldprec = std::cout.precision();
for(int b=0;b<SUMMA.NHIST;b++){
if ( !SUMMA.histN[b] ) continue;
double sec = SUMMA.histUs[b]/1.0e6, g = SUMMA.histBytes[b]/1.0e9;
double lo = (double)(1ull<<b);
char sz[32]; if (lo>=1048576) snprintf(sz,32,"%6.1f MB",lo/1048576.); else if (lo>=1024) snprintf(sz,32,"%6.1f KB",lo/1024.); else snprintf(sz,32,"%6.0f B ",lo);
std::cout << GridLogMessage << " >=" << sz
<< std::setw(8) << SUMMA.histN[b]
<< std::setw(10) << std::setprecision(3) << g
<< std::setw(9) << std::setprecision(3) << sec
<< std::setw(9) << std::setprecision(3) << (sec>0 ? g/sec : 0.0)
<< std::setw(8) << std::setprecision(3) << (ring>0 ? 100.0*sec/ring : 0.0) << std::endl;
}
std::cout.precision(oldprec);
}
};