Re: Crash report for some ICU-52 (debian8) COLLATE and work_mem values

	Peter Geoghegan wrote:

> Does the crash always have ucol_strcollUseLatin1UTF8() in its backtrace?

AFAICS, yes.

The test that iterates over collations produces two kinds of core files,
some of them are 289MB large, some others are 17GB large.
shared_buffers is only 128MB and work_mem 128MB, 
so 289MB is not surprising but 17GB seems excessive.
The box has 16GB of physical mem and 8GB of swap.

I haven't checked all core files because they exhaust the disk
space before completion of the test, but a typical backtrace for
the biggest ones looks like the following, with the segfaults
happening in memcpy:

Program terminated with signal SIGSEGV, Segmentation fault.
#0  __memcpy_sse2_unaligned ()
    at ../sysdeps/x86_64/multiarch/memcpy-sse2-unaligned.S:35
(gdb) #0  __memcpy_sse2_unaligned ()
    at ../sysdeps/x86_64/multiarch/memcpy-sse2-unaligned.S:35
#1  0x00007fc1db02be6b in memcpy (__len=8589934592, __src=0x7fbc6f4a2010,
    __dest=<optimized out>) at
/usr/include/x86_64-linux-gnu/bits/string3.h:51
#2  ucol_CEBuf_Expand (ci=<optimized out>, status=0x7ffd90777128,
    b=0x7ffd907751e0) at ucol.cpp:7009
#3  UCOL_CEBUF_PUT (status=0x7ffd90777128, ci=0x7ffd90776460, ce=1493173509,
    b=0x7ffd907751e0) at ucol.cpp:7022
#4  ucol_strcollRegular (sColl=sColl@entry=0x7ffd90776460,
    tColl=tColl@entry=0x7ffd90776610, status=status@entry=0x7ffd90777128)
    at ucol.cpp:7163
#5  0x00007fc1db031177 in ucol_strcollRegularUTF8 (coll=0x1371af0,
    source=source@entry=0x273d379 "콗喩zx㎍",
    sourceLength=sourceLength@entry=11, target=<optimized out>,
    targetLength=targetLength@entry=8, status=status@entry=0x7ffd90777128)
    at ucol.cpp:8023
#6  0x00007fc1db032d36 in ucol_strcollUseLatin1UTF8 (status=<optimized out>,
    tLen=<optimized out>, target=<optimized out>, sLen=<optimized out>,
    source=<optimized out>, coll=<optimized out>) at ucol.cpp:8108
#7  ucol_strcollUTF8_52 (coll=<optimized out>,
    source=source@entry=0x273d379 "콗喩zx㎍", sourceLength=<optimized out>,
    sourceLength@entry=11, target=<optimized out>,
    target@entry=0x273d409 "쳭喩zz", targetLength=targetLength@entry=8,
    status=status@entry=0x7ffd90777128) at ucol.cpp:8770
#8  0x00000000007cc7b4 in varstrfastcmp_locale (x=41145208, y=41145352,
    ssup=<optimized out>) at varlena.c:2139
#9  0x0000000000817138 in ApplySortAbbrevFullComparator (ssup=0x136bd98,
    isNull2=<optimized out>, datum2=<optimized out>, isNull1=<optimized out>, 
    datum1=<optimized out>) at
../../../../src/include/utils/sortsupport.h:263
#10 comparetup_datum (a=0x7fc1c642d210, b=0x7fc1c642d228, 
    state=<optimized out>) at tuplesort.c:4350
#11 0x0000000000815aef in qsort_tuple (a=0x7fc1c642d210, n=<optimized out>, 
    n@entry=2505, cmp_tuple=cmp_tuple@entry=0x817030 <comparetup_datum>, 
    state=state@entry=0x136bb88) at qsort_tuple.c:104
#12 0x0000000000815c1f in qsort_tuple (a=0x7fc1c6413020, n=<optimized out>, 
    n@entry=5279, cmp_tuple=cmp_tuple@entry=0x817030 <comparetup_datum>, 
    state=state@entry=0x136bb88) at qsort_tuple.c:191
#13 0x0000000000815c1f in qsort_tuple (a=0x7fc1c63f27e8, n=<optimized out>, 
    n@entry=103353, cmp_tuple=cmp_tuple@entry=0x817030 <comparetup_datum>, 
    state=state@entry=0x136bb88) at qsort_tuple.c:191
#14 0x0000000000815c1f in qsort_tuple (a=0x7fc1c5f423c8, n=<optimized out>, 
    n@entry=503456, cmp_tuple=cmp_tuple@entry=0x817030 <comparetup_datum>, 
    state=state@entry=0x136bb88) at qsort_tuple.c:191
#15 0x0000000000815c1f in qsort_tuple (a=0x7fc1c34ae048, n=<optimized out>, 
    cmp_tuple=0x817030 <comparetup_datum>, state=state@entry=0x136bb88)
    at qsort_tuple.c:191
#16 0x000000000081873b in tuplesort_sort_memtuples (
    state=state@entry=0x136bb88) at tuplesort.c:3410
#17 0x0000000000818907 in dumpbatch (alltuples=0 '\000', state=0x136bb88)
    at tuplesort.c:3087
#18 dumptuples (state=state@entry=0x136bb88, 
    alltuples=alltuples@entry=0 '\000') at tuplesort.c:2970
#19 0x0000000000818b81 in puttuple_common (state=state@entry=0x136bb88, 
    tuple=tuple@entry=0x7ffd90777470) at tuplesort.c:1719
#20 0x000000000081a6f1 in tuplesort_putdatum (state=0x136bb88, 
    val=<optimized out>, isNull=<optimized out>) at tuplesort.c:1558
#21 0x00000000005e91ec in advance_aggregates (
    aggstate=aggstate@entry=0x13731f8, pergroup=pergroup@entry=0x1376008, 
    pergroups=0x0) at nodeAgg.c:1023
#22 0x00000000005eac03 in agg_retrieve_direct (aggstate=0x13731f8)
    at nodeAgg.c:2402
#23 ExecAgg (node=node@entry=0x13731f8) at nodeAgg.c:2117
#24 0x00000000005e2378 in ExecProcNode (node=node@entry=0x13731f8)
    at execProcnode.c:539
#25 0x00000000005ddf1e in ExecutePlan (execute_once=<optimized out>, 
    dest=0x132f368, direction=<optimized out>, numberTuples=0, 
    sendTuples=<optimized out>, operation=CMD_SELECT, 
    use_parallel_mode=<optimized out>, planstate=0x13731f8, estate=0x1372fe8)
    at execMain.c:1693
#26 standard_ExecutorRun (queryDesc=0x1350938, direction=<optimized out>, 
    count=0, execute_once=<optimized out>) at execMain.c:362
#27 0x00000000006f924c in PortalRunSelect (portal=portal@entry=0x1362d98, 
    forward=forward@entry=1 '\001', count=0, count@entry=9223372036854775807, 
    dest=dest@entry=0x132f368) at pquery.c:932
#28 0x00000000006fa5f0 in PortalRun (portal=0x1362d98, 
    count=9223372036854775807, isTopLevel=<optimized out>, 
    run_once=<optimized out>, dest=0x132f368, altdest=0x132f368, 
    completionTag=0x7ffd90777990 "") at pquery.c:773
#29 0x00000000006f7da1 in exec_execute_message (max_rows=9223372036854775807, 
    portal_name=<optimized out>) at postgres.c:1984
#30 PostgresMain (argc=3, argv=0x7fffffffffffffff, dbname=0x12cb288 "mlists", 
    username=0x132f368 "") at postgres.c:4153
#31 0x000000000047803f in BackendRun (port=0x12c4f30) at postmaster.c:4357
#32 BackendStartup (port=0x12c4f30) at postmaster.c:4029
#33 ServerLoop () at postmaster.c:1753
#34 0x0000000000692a82 in PostmasterMain (argc=argc@entry=3, 
    argv=argv@entry=0x129d330) at postmaster.c:1361
#35 0x0000000000478f8e in main (argc=3, argv=0x129d330) at main.c:228


Best regards,
-- 
Daniel Vérité
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