GCC memory consumption increased by recent patch!

gcctest@suse.de gcctest@suse.de
Mon Jan 24 00:46:00 GMT 2005


Hi,
Comparing memory consumption on compilation of combine.i and generate-3.4.ii I got:


comparing combine.c compilation at -O0 level:
    Overall memory needed: 24617k
    Peak memory use before GGC: 9345k
    Peak memory use after GGC: 8659k
    Maximum of released memory in single GGC run: 2864k
    Garbage: 41677k
    Leak: 6395k
    Overhead: 5774k
    GGC runs: 329

comparing combine.c compilation at -O1 level:
    Overall memory needed: 26697k -> 26701k
    Peak memory use before GGC: 9223k
    Peak memory use after GGC: 8716k
    Maximum of released memory in single GGC run: 2024k -> 2023k
    Garbage: 65997k -> 65948k
    Leak: 6750k -> 6749k
    Overhead: 10442k -> 10433k
    GGC runs: 520

comparing combine.c compilation at -O2 level:
    Overall memory needed: 29485k -> 29489k
    Peak memory use before GGC: 12656k
    Peak memory use after GGC: 12530k
    Maximum of released memory in single GGC run: 2551k -> 2550k
    Garbage: 80119k -> 80084k
    Leak: 6574k -> 6573k
    Overhead: 14270k -> 14274k
    GGC runs: 523

comparing combine.c compilation at -O3 level:
  Overall memory allocated via mmap and sbrk increased from 20212k to 20324k, overall 0.55%
    Overall memory needed: 20212k -> 20324k
    Peak memory use before GGC: 12785k
    Peak memory use after GGC: 12530k
    Maximum of released memory in single GGC run: 3348k
    Garbage: 108285k -> 108249k
    Leak: 7100k -> 7098k
    Overhead: 19134k -> 19130k
    GGC runs: 591 -> 589

comparing insn-attrtab.c compilation at -O0 level:
    Overall memory needed: 114132k
    Peak memory use before GGC: 74734k
    Peak memory use after GGC: 45480k
    Maximum of released memory in single GGC run: 39341k
    Garbage: 152710k
    Leak: 10950k
    Overhead: 19973k
    GGC runs: 274

comparing insn-attrtab.c compilation at -O1 level:
    Overall memory needed: 125156k
    Peak memory use before GGC: 83493k
    Peak memory use after GGC: 69209k
    Maximum of released memory in single GGC run: 40528k
    Garbage: 435210k -> 435208k
    Leak: 11295k
    Overhead: 76689k -> 76677k
    GGC runs: 406

comparing insn-attrtab.c compilation at -O2 level:
    Overall memory needed: 147340k
    Peak memory use before GGC: 98331k
    Peak memory use after GGC: 83448k
    Maximum of released memory in single GGC run: 39290k
    Garbage: 481614k -> 481613k
    Leak: 11225k
    Overhead: 84770k -> 84770k
    GGC runs: 342

comparing insn-attrtab.c compilation at -O3 level:
    Overall memory needed: 148976k
    Peak memory use before GGC: 98333k
    Peak memory use after GGC: 83449k
    Maximum of released memory in single GGC run: 39291k
    Garbage: 482650k -> 482648k
    Leak: 11263k
    Overhead: 84918k -> 84918k
    GGC runs: 348

comparing Gerald's testcase PR8361 compilation at -O0 level:
    Overall memory needed: 111088k
    Peak memory use before GGC: 86882k
    Peak memory use after GGC: 85932k
    Maximum of released memory in single GGC run: 19283k
    Garbage: 246347k
    Leak: 55492k
    Overhead: 43354k
    GGC runs: 368

comparing Gerald's testcase PR8361 compilation at -O1 level:
    Overall memory needed: 104617k -> 104605k
    Peak memory use before GGC: 85965k
    Peak memory use after GGC: 84929k
    Maximum of released memory in single GGC run: 18947k
    Garbage: 456900k -> 456613k
    Leak: 56813k -> 56823k
    Overhead: 66487k -> 66417k
    GGC runs: 541

comparing Gerald's testcase PR8361 compilation at -O2 level:
    Overall memory needed: 104681k
    Peak memory use before GGC: 85965k
    Peak memory use after GGC: 84929k
    Maximum of released memory in single GGC run: 18947k
    Garbage: 491678k -> 491371k
    Leak: 57399k -> 57403k
    Overhead: 75938k -> 75802k
    GGC runs: 590 -> 589

comparing Gerald's testcase PR8361 compilation at -O3 level:
    Overall memory needed: 112401k -> 112397k
    Peak memory use before GGC: 92703k
    Peak memory use after GGC: 86223k
    Maximum of released memory in single GGC run: 19712k
    Garbage: 507176k -> 506904k
    Leak: 57560k -> 57579k
    Overhead: 77497k -> 77425k
    GGC runs: 574

Head of changelog is:

--- /usr/src/SpecTests/sandbox-britten-memory/x86_64/mem-result/ChangeLog	2005-01-23 19:14:17.000000000 +0000
+++ /usr/src/SpecTests/sandbox-britten-memory/gcc/gcc/ChangeLog	2005-01-23 23:44:51.000000000 +0000
@@ -1,8 +1,38 @@
 2005-01-23  Kazu Hirata  <kazu@cs.umass.edu>
 
+	* flow.c (regset_bytes, regset_size): Remove.
+
+	* cfganal.c: Fix a reference to Harvey's paper.
+
+2005-01-23  Steven Bosscher  <stevenb@suse.de>
+
+	PR rtl-optimization/19464
+	* tree-optimize.c (init_tree_optimization_passes): Add one more
+	copyrename pass just before out-of-ssa.
+
+2005-01-23  Joseph S. Myers  <joseph@codesourcery.com>
+
+	PR bootstrap/18058
+	* recog.c (recog_memoized): Don't define if GENERATOR_FILE.
+	* ggc-none.c (ggc_free): Define.
+
+2005-01-23  Kazu Hirata  <kazu@cs.umass.edu>
+
 	* cse.c (max_reg, max_insn_uid): Remove.
 	(cse_main): Don't access max_reg or max_insn_uid.
 
+	* c-common.c (explicit_flag_signed_bitfields,
+	lang_statement_code_p, lang_expand_function_end): Remove.
+	* c-common.h: Remove the corresponding declarations.
+	* c-opts.c (c_common_handle_option): Remove all write access
+	to explicit_flag_signed_bitfields.
+
+	* cgraph.c (cgraph_varpool_n_nodes): Remove.
+	(cgraph_varpool_node): Don't access cgraph_varpool_n_nodes.
+	* cgraph.h: Remove the corresponding declaration.
+
+	* gcse.c (null_pointer_info): Remove.
+
 2005-01-23  Roger Sayle  <roger@eyesopen.com>
 	    Eric Botcazou  <ebotcazou@libertysurf.fr>
 

I am friendly script caring about memory consumption in GCC.  Please contact
jh@suse.cz if something is going wrong.

The results can be reproduced by building compiler with
--enable-gather-detailed-mem-stats targetting x86-64 and compiling preprocessed
combine.c or testcase from PR8632 with:

-fmem-report --param=ggc-min-heapsize=1024 --param=ggc-min-expand=1 -Ox -Q

The memory consumption summary appears in the dump after detailed listing of
the places they are allocated in.  Peak memory consumption is actually computed
by looking for maximal value in {GC XXXX -> YYYY} report.

Yours testing script.



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