I'm debugging this problem with stalled transactions waiting on locks which
have already been granted and I'm puzzled by something. What is this PGPROC
entry from?
It's not a real process (pid is 0) and it's not garbage either (prev and next
both point to a real PGPROC entry, namely MyProc which as you can see is
waiting for this PGPROC).
(gdb) p *(PGPROC*)(ShmemBase + MyProc->links.prev)
$2 = {links = {prev = 2520941752, next = 2520941752}, sem = {semId = 1, semNum = 0}, waitStatus = 0, xid = 0, xmin = 0,
pid= 0, databaseId = 0, roleId = 0, inCommit = 0 '\0', inVacuum = 0 '\0', isAutovacuum = 0 '\0', lwWaiting = 0 '\0',
lwExclusive= 2 '\002', lwWaitLink = 0x0, waitLock = 0x2, waitProcLock = 0x0, waitLockMode = 0, heldLocks = 0,
myProcLocks= {{prev = 0, next = 1}, { prev = 4294967296, next = 0}, {prev = 3028785127, next = 360654}, {prev =
73183493944770560,next = 137438953600}, { prev = 2520929504, next = 2520929072}, {prev = 2520940536, next =
2520940536},{prev = 1, next = 0}, {prev = 0, next = 4294967296}, {prev = 4294967296, next = 0}, {prev = 2, next =
0},{prev = 0, next = 0}, {prev = 1, next = 4294967296}, { prev = 0, next = 4000475635}, {prev = 360707, next =
73183493944770560},{prev = 128, next = 2520933680}, {prev = 2520933680, next = 2520914616}}, subxids = {overflowed
=-72 '�', nxids = 0, xids = {0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 1, 0, 0,
1626942462,0, 16384, 16430, 0, 16777216, 2, 0, 2520930944, 0, 2520930944, 0, 2520914784, 0, 2520914784, 0, 0, 0,
0,1, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0}}}
(gdb) p MyProc-ShmemBase
$3 = (PGPROC *) 0xff9ac36e36e264b8
(gdb) p (unsigned long)MyProc-ShmemBase
$4 = 2520941752
-- Gregory Stark EnterpriseDB http://www.enterprisedb.com
