Re: Write Ahead Logging for Hash Indexes

Hi Amit,

Thanks for working on this.

When building with --enable-cassert, I get compiler warning:

hash.c: In function 'hashbucketcleanup':
hash.c:722: warning: 'new_bucket' may be used uninitialized in this function

After an intentionally created crash, I get an Assert triggering:

TRAP: FailedAssertion("!(((freep)[(bitmapbit)/32] &
(1<<((bitmapbit)%32))))", File: "hashovfl.c", Line: 553)

freep[0] is zero and bitmapbit is 16.

With this backtrace:

(gdb) bt
#0 0x0000003838c325e5 in raise (sig=6) at
../nptl/sysdeps/unix/sysv/linux/raise.c:64
#1 0x0000003838c33dc5 in abort () at abort.c:92
#2 0x000000000081a8fd in ExceptionalCondition (conditionName=<value
optimized out>, errorType=<value optimized out>, fileName=<value optimized
out>,
lineNumber=<value optimized out>) at assert.c:54
#3 0x00000000004a4199 in _hash_freeovflpage (rel=0x7f3f745d86b8,
bucketbuf=198, ovflbuf=199, wbuf=198, itups=0x7ffc258fa090,
itup_offsets=0x126e8a8,
tups_size=0x7ffc258f93d0, nitups=70, bstrategy=0x12ba320) at
hashovfl.c:553
#4 0x00000000004a4c32 in _hash_squeezebucket (rel=<value optimized out>,
bucket=38, bucket_blkno=56, bucket_buf=198, bstrategy=0x12ba320)
at hashovfl.c:1010
#5 0x00000000004a042a in hashbucketcleanup (rel=0x7f3f745d86b8,
bucket_buf=198, bucket_blkno=56, bstrategy=0x12ba320, maxbucket=96,
highmask=127,
lowmask=63, tuples_removed=0x7ffc258fc1c8,
num_index_tuples=0x7ffc258fc1c0, bucket_has_garbage=0 '\000', delay=1
'\001',
callback=0x5e9bd0 <lazy_tid_reaped>, callback_state=0x126e248) at
hash.c:937
#6 0x00000000004a07e7 in hashbulkdelete (info=0x7ffc258fc2b0, stats=0x0,
callback=0x5e9bd0 <lazy_tid_reaped>, callback_state=0x126e248) at hash.c:580
#7 0x00000000005e98c5 in lazy_vacuum_index (indrel=0x7f3f745d86b8,
stats=0x126ecc0, vacrelstats=0x126e248) at vacuumlazy.c:1599
#8 0x00000000005ea7f9 in lazy_scan_heap (onerel=<value optimized out>,
options=<value optimized out>, params=0x12ba290, bstrategy=<value optimized
out>)
at vacuumlazy.c:1291
#9 lazy_vacuum_rel (onerel=<value optimized out>, options=<value optimized
out>, params=0x12ba290, bstrategy=<value optimized out>) at vacuumlazy.c:255
#10 0x00000000005e8939 in vacuum_rel (relid=17329, relation=0x7ffc258fcbd0,
options=99, params=0x12ba290) at vacuum.c:1399
#11 0x00000000005e8d01 in vacuum (options=99, relation=0x7ffc258fcbd0,
relid=<value optimized out>, params=0x12ba290, va_cols=0x0,
bstrategy=<value optimized out>, isTopLevel=1 '\001') at vacuum.c:307
#12 0x00000000006a07f1 in autovacuum_do_vac_analyze () at autovacuum.c:2823
#13 do_autovacuum () at autovacuum.c:2341
#14 0x00000000006a0f9c in AutoVacWorkerMain (argc=<value optimized out>,
argv=<value optimized out>) at autovacuum.c:1656
#15 0x00000000006a1116 in StartAutoVacWorker () at autovacuum.c:1461
#16 0x00000000006afb00 in StartAutovacuumWorker (postgres_signal_arg=<value
optimized out>) at postmaster.c:5323
#17 sigusr1_handler (postgres_signal_arg=<value optimized out>) at
postmaster.c:5009
#18 <signal handler called>
#19 0x0000003838ce1503 in __select_nocancel () at
../sysdeps/unix/syscall-template.S:82
#20 0x00000000006b0ec0 in ServerLoop (argc=<value optimized out>,
argv=<value optimized out>) at postmaster.c:1657
#21 PostmasterMain (argc=<value optimized out>, argv=<value optimized out>)
at postmaster.c:1301
#22 0x0000000000632e88 in main (argc=4, argv=0x11f4d50) at main.c:228

Cheers,

Jeff