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author | Simon Marlow <marlowsd@gmail.com> | 2011-11-28 16:48:43 +0000 |
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committer | Simon Marlow <marlowsd@gmail.com> | 2011-11-29 12:21:18 +0000 |
commit | 50de6034343abc93a7b01daccff34121042c0e7c (patch) | |
tree | 24496a5fc6bc39c6baaa574608e53c5d76c169f6 /rts/Exception.cmm | |
parent | 1c2b838131134d44004dfdff18c302131478390d (diff) | |
download | haskell-50de6034343abc93a7b01daccff34121042c0e7c.tar.gz |
Make profiling work with multiple capabilities (+RTS -N)
This means that both time and heap profiling work for parallel
programs. Main internal changes:
- CCCS is no longer a global variable; it is now another
pseudo-register in the StgRegTable struct. Thus every
Capability has its own CCCS.
- There is a new built-in CCS called "IDLE", which records ticks for
Capabilities in the idle state. If you profile a single-threaded
program with +RTS -N2, you'll see about 50% of time in "IDLE".
- There is appropriate locking in rts/Profiling.c to protect the
shared cost-centre-stack data structures.
This patch does enough to get it working, I have cut one big corner:
the cost-centre-stack data structure is still shared amongst all
Capabilities, which means that multiple Capabilities will race when
updating the "allocations" and "entries" fields of a CCS. Not only
does this give unpredictable results, but it runs very slowly due to
cache line bouncing.
It is strongly recommended that you use -fno-prof-count-entries to
disable the "entries" count when profiling parallel programs. (I shall
add a note to this effect to the docs).
Diffstat (limited to 'rts/Exception.cmm')
-rw-r--r-- | rts/Exception.cmm | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/rts/Exception.cmm b/rts/Exception.cmm index 1192db732c..78907c4ba7 100644 --- a/rts/Exception.cmm +++ b/rts/Exception.cmm @@ -369,7 +369,7 @@ stg_catchzh /* Set up the catch frame */ Sp = Sp - SIZEOF_StgCatchFrame; - SET_HDR(Sp,stg_catch_frame_info,W_[CCCS]); + SET_HDR(Sp,stg_catch_frame_info,CCCS); StgCatchFrame_handler(Sp) = R2; StgCatchFrame_exceptions_blocked(Sp) = @@ -427,7 +427,7 @@ stg_raisezh */ if (RtsFlags_ProfFlags_showCCSOnException(RtsFlags) != 0::I32) { SAVE_THREAD_STATE(); - foreign "C" fprintCCS_stderr(W_[CCCS] "ptr", + foreign "C" fprintCCS_stderr(CCCS "ptr", exception "ptr", CurrentTSO "ptr") []; LOAD_THREAD_STATE(); |