From: Dmitriy Sarafannikov <d.sarafannikov@bk.ru>
To: PostgreSQL Bugs <pgsql-bugs@postgresql.org>
Subject: Too many files in pg_replslot folder
Date: Thu, 10 Mar 2016 17:49:18 +0300
Message-ID: <1457621358.355011041@f382.i.mail.ru> (raw)
List-Unsubscribe: <mailto:majordomo@postgresql.org?body=unsub%20pgsql-bugs>
Hi, all.
I tried to test logical replication with 'test_decoding' plugin.
I created logical slot and launched pg_recvlogical utility on ~8 hours.
When i tried to drop replication slot via pg_drop_replication_slot, backend ate my disk on 100% and didn't want to release him.
I saw via strace, that he deletes files:
lstat("pg_replslot/test_slot.tmp/xid-2917185562-lsn-4981-AE000000.snap", {st_mode=S_IFREG|0600, st_size=169, ...}) = 0
unlink("pg_replslot/test_slot.tmp/xid-2917185562-lsn-4981-AE000000.snap") = 0
lstat("pg_replslot/test_slot.tmp/xid-2915407454-lsn-497F-14000000.snap", {st_mode=S_IFREG|0600, st_size=161, ...}) = 0
unlink("pg_replslot/test_slot.tmp/xid-2915407454-lsn-497F-14000000.snap") = 0
lstat("pg_replslot/test_slot.tmp/xid-2915727847-lsn-497F-8C000000.snap", {st_mode=S_IFREG|0600, st_size=169, ...}) = 0
unlink("pg_replslot/test_slot.tmp/xid-2915727847-lsn-497F-8C000000.snap") = 0
lstat("pg_replslot/test_slot.tmp/xid-2919565207-lsn-4984-94000000.snap", {st_mode=S_IFREG|0600, st_size=177, ...}) = 0
unlink("pg_replslot/test_slot.tmp/xid-2919565207-lsn-4984-94000000.snap") = 0
lstat("pg_replslot/test_slot.tmp/xid-2915738746-lsn-497F-8D000000.snap", {st_mode=S_IFREG|0600, st_size=177, ...}) = 0
unlink("pg_replslot/test_slot.tmp/xid-2915738746-lsn-497F-8D000000.snap") = 0
lstat("pg_replslot/test_slot.tmp/xid-2917437588-lsn-4981-F2000000.snap", {st_mode=S_IFREG|0600, st_size=161, ...}) = 0
unlink("pg_replslot/test_slot.tmp/xid-2917437588-lsn-4981-F2000000.snap") = 0
lstat("pg_replslot/test_slot.tmp/xid-2917359031-lsn-4981-E5000000.snap", {st_mode=S_IFREG|0600, st_size=161, ...}) = 0
unlink("pg_replslot/test_slot.tmp/xid-2917359031-lsn-4981-E5000000.snap") = 0
lstat("pg_replslot/test_slot.tmp/xid-2917766393-lsn-4982-84000000.snap", {st_mode=S_IFREG|0600, st_size=177, ...}) = 0
unlink("pg_replslot/test_slot.tmp/xid-2917766393-lsn-4982-84000000.snap") = 0
lstat("pg_replslot/test_slot.tmp/xid-2915337440-lsn-497F-8000000.snap", {st_mode=S_IFREG|0600, st_size=169, ...}) = 0
unlink("pg_replslot/test_slot.tmp/xid-2915337440-lsn-497F-8000000.snap") = 0
lstat("pg_replslot/test_slot.tmp/xid-2916494069-lsn-4980-C3000000.snap", {st_mode=S_IFREG|0600, st_size=177, ...}) = 0
unlink("pg_replslot/test_slot.tmp/xid-2916494069-lsn-4980-C3000000.snap") = 0
lstat("pg_replslot/test_slot.tmp/xid-2916877166-lsn-4981-4F000000.snap", {st_mode=S_IFREG|0600, st_size=169, ...}) = 0
unlink("pg_replslot/test_slot.tmp/xid-2916877166-lsn-4981-4F000000.snap") = 0
He seemed to be in infinite loop. 1109428 files were in the slot folder.
It looks like abnormal behavior. Why are so many files?
Maybe i'm doing something wrong? Or maybe it is bug?
How i can avoid this?
And wal sender ate ~800 mb of memory during this test. Is it leakage?
version
-----------------------------------------------------------------------------------------------
PostgreSQL 9.4.6 on x86_64-unknown-linux-gnu, compiled by gcc (Debian 4.9.2-10) 4.9.2, 64-bit
Thanks for advance and sorry for my English.
Regards,
Dmitriy Sarafannikov
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Reply to all the recipients using the --to and --cc options:
reply via email
To: pgsql-bugs@postgresql.org
Cc: d.sarafannikov@bk.ru
Subject: Re: Too many files in pg_replslot folder
In-Reply-To: <1457621358.355011041@f382.i.mail.ru>
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
This inbox is served by DDX for PostgreSQL; see mirroring instructions
for how to clone and mirror all data and code used for this inbox