[pgpool-general: 7732] Re: Out of memory

Tatsuo Ishii ishii at sraoss.co.jp
Thu Sep 30 06:38:09 JST 2021


I am not familiar with python. It would be helpful if you can share
the pgpool log with log_client_messages enabled while running the
python session. This will show what messages the python client sends
to pgpool.

> There is nothing special, it's a python application using psycopg to
> connect.
> 
> I've made a very simple test here, using:
> Python 2.7.17
> Psycopg 2.8.6
> We have another setup running with Python 3, it seems to have the same
> result.
> 
> $ bin/python
> Python 2.7.17 (default, Oct 20 2019, 14:16:51)
> [GCC 5.5.0] on linux2
> Type "help", "copyright", "credits" or "license" for more information.
>>>> import psycopg2
>>>> conn = psycopg2.connect("dbname='XXXX' user='XXXX'
> host='192.168.XXX.XXX' password='XXXXXX' port='9999'")
>>>> cur = conn.cursor()
>>>> cur.execute("""SELECT * from XX""")
> 
> This is a very simple select, it returns 27 results with 2 columns, an ID e
> a string (two characters in each row)
> 
> pgpool 3.7.3:
> After "psycopg.connect":
> root      3230  0.0  0.0  36200  2544 ?        S    10:16   0:00 pgpool:
> XXXX XXXX 192.168.XXX.XXX(59576) idle
> 
> After "cur.execute":
> root      3230  0.0  0.0  41400  9272 ?        S    10:16   0:00 pgpool:
> XXXX XXXX 192.168.XXX.XXX(59576) idle in transaction
> 
> pgpool 4.1.8:
> After "psycopg.connect":
> root      5317  0.0  0.0  39044  2564 ?        S    11:35   0:00 pgpool:
> zope nube 192.168.XXX.XXX(54784) idle
> 
> After "cur.execute":
> root      5317  0.0  0.2  72200 37040 ?        S    11:35   0:00 pgpool:
> zope nube 192.168.XXX.XXX(54784) idle in transaction
> 
> Do you think this is enough to reproduce? Or do you need something
> different? Let me know, I'm here to help.
> 
> 
> On Wed, Sep 29, 2021 at 8:54 AM Tatsuo Ishii <ishii at sraoss.co.jp> wrote:
> 
>> So enable_shared_relcache is irrelevant.
>>
>> Problem is, I cannot reproduce your problem here. It would be greately
>> helpful if you can provide a self containing test case. If you cannot,
>> I would like to find a pattern (query) which triggers the problem.
>>
>> - Does the query use extended protocol?
>>
>> - What kind of queries does the application use?
>>   INSERT/UPDATE/SELECT/DELETE??
>>
>> - IS there anything special with the application?
>>
>> > I tested 4.1.0 now and it shows the same behaviour.
>> >
>> > Also, disabling enable_shared_relcache did not solve the problem.
>> >
>> > On Tue, Sep 28, 2021 at 9:10 PM Tatsuo Ishii <ishii at sraoss.co.jp> wrote:
>> >
>> >> Ok. Let's assume 4.1.0 introduced the problem for now (it's still
>> >> possible that certain minor version of 4.1 introduced the issue, but
>> >> for now I neglect the possibility).
>> >>
>> >> 4.1.0 includes following major changes especially related to memory.
>> >>
>> >> (1) Shared relation cache allows to reuse relation cache among
>> >>     sessions to reduce internal queries against PostgreSQL system
>> >>     catalogs.
>> >>
>> >>     (this feature uses shared memory even if memory_cache_enabled =
>> off).
>> >>
>> >> (2) Have separate SQL parser for DML statements to eliminate
>> >>     unnecessary parsing effort.
>> >>
>> >>     (this allocates additional process memory for certain query)
>> >>
>> >> For (1) we can disable the feature by:
>> >>
>> >> enable_shared_relcache = off
>> >>
>> >> Can you try it out?
>> >>
>> >> > I did those tests:
>> >> > 4.0.15 is running fine, when I upgraded to 4.1.8 it started to
>> consume a
>> >> > lot of memory.
>> >> >
>> >> > On Tue, Sep 28, 2021 at 8:30 AM Tatsuo Ishii <ishii at sraoss.co.jp>
>> wrote:
>> >> >
>> >> >> Ok. 4.2.1 consumes 10 times of memory than 3.7.3 (maybe 5, not 10
>> >> >> because in your test connections of 4.2.1 is twice of 3.7.3).
>> >> >>
>> >> >> Next thing I need to know is, from which version of pgpool started to
>> >> >> consume lot of memory.  Is it possible to run the same test against
>> >> >> 4.0 and 4.1? Ideally from which version, including minor version will
>> >> >> be a lot helpful. I wish I could the test myself but I don't know to
>> >> >> do it on my environment.
>> >> >>
>> >> >> > Sure.
>> >> >> >
>> >> >> > On 3.7.3:
>> >> >> > $ ps aux | grep pgpool | awk '{sum += $6}END{print sum}'
>> >> >> > 896752
>> >> >> >
>> >> >> > On 4.2.1:
>> >> >> > $ ps aux | grep pgpool | awk '{sum += $6}END{print sum}'
>> >> >> > 9969280
>> >> >> >
>> >> >> >
>> >> >> > On Mon, Sep 27, 2021 at 11:41 PM Tatsuo Ishii <ishii at sraoss.co.jp>
>> >> >> wrote:
>> >> >> >
>> >> >> >> Ok, let's see how much RSS pgpool consume in total. Can you share
>> the
>> >> >> >> result of the command for both pgpool 4.2 and 3.7?
>> >> >> >>
>> >> >> >> ps aux | grep pgpool | awk '{sum += $6}END{print sum}'
>> >> >> >>
>> >> >> >> > I see.
>> >> >> >> >
>> >> >> >> > The problem is, the OOM happens when all RAM is already
>> >> compromised by
>> >> >> >> > pgpool (all 16Gb of RAM is dedicated to pgpool), so any common
>> >> request
>> >> >> >> will
>> >> >> >> > die anyway.
>> >> >> >> >
>> >> >> >> > It happens on versions: 4.2.5 and 4.2.1. Now, I'm running the
>> same
>> >> >> >> > application on 3.7.3 and it's running great.
>> >> >> >> >
>> >> >> >> > I don't know if it helps, but just to demonstrate the amount of
>> >> RAM is
>> >> >> >> > necessary to run a few connections I created another VM, and
>> >> >> comparing:
>> >> >> >> >
>> >> >> >> > 62 active connections running on 4.2.1 (same behaviour on
>> 4.2.5):
>> >> >> >> > $ vmstat -a -SM
>> >> >> >> > procs -----------memory---------- ---swap-- -----io----
>> -system--
>> >> >> >> > ------cpu-----
>> >> >> >> >  r  b   swpd   free  inact active   si   so    bi    bo   in
>>  cs
>> >> us
>> >> >> sy
>> >> >> >> id
>> >> >> >> > wa st
>> >> >> >> >  0  0      0   4829    173  10772    0    0     2     1   68
>>  56
>> >> 1
>> >> >> 1
>> >> >> >> 99
>> >> >> >> >  0  0
>> >> >> >> >
>> >> >> >> > 31 active connections running on 3.7.3:
>> >> >> >> > $ vmstat -a -SM
>> >> >> >> > procs -----------memory---------- ---swap-- -----io----
>> -system--
>> >> >> >> > ------cpu-----
>> >> >> >> >  r  b   swpd   free  inact active   si   so    bi    bo   in
>>  cs
>> >> us
>> >> >> sy
>> >> >> >> id
>> >> >> >> > wa st
>> >> >> >> >  0  0      0  15174     73    635    0    0     1     1   76
>> 3
>> >> 0
>> >> >> 0
>> >> >> >> 100
>> >> >> >> >  0  0
>> >> >> >> >
>> >> >> >> > Both are running basically the same application.
>> >> >> >> >
>> >> >> >> > Seeing the RAM consumption of 3.7.3, it does not seem to be
>> >> receiving
>> >> >> >> such
>> >> >> >> > a big requests. Is there a way to track it down?
>> >> >> >> >
>> >> >> >> >
>> >> >> >> >
>> >> >> >> > On Mon, Sep 27, 2021 at 9:07 AM Tatsuo Ishii <
>> ishii at sraoss.co.jp>
>> >> >> wrote:
>> >> >> >> >
>> >> >> >> >> At this point I cannot judge whether the problem is caused by a
>> >> >> pgpool
>> >> >> >> >> bug or client's resource request is too much.
>> >> >> >> >>
>> >> >> >> >> Typical bug which requests too much memory allocation is not
>> >> >> something
>> >> >> >> >> like this because 33947648 = 32MB memory request itself is not
>> >> >> insane.
>> >> >> >> >>
>> >> >> >> >> > Sep 24 09:14:10 pgpool pgpool[12650]: [426-2] 2021-09-24
>> >> 09:14:10:
>> >> >> pid
>> >> >> >> >> > 12650: DETAIL:  Failed on request of size 33947648.
>> >> >> >> >>
>> >> >> >> >> (Please let us know what version of Pgpool-II you are using
>> >> because
>> >> >> >> >> it's important information to identify any known bug).
>> >> >> >> >>
>> >> >> >> >> In the mean time, however, I think 32MB memory request is not
>> very
>> >> >> >> >> common in pgpool. One thing I wonder is, whether your
>> application
>> >> >> >> >> issues SQL which requires large memory: e.g. very long SQL
>> >> statement,
>> >> >> >> >> COPY for large data set. They will request large read/write
>> >> buffer in
>> >> >> >> >> pgpool.
>> >> >> >> >>
>> >> >> >> >> > We saw both, but pgpool aborting is way more common:
>> >> >> >> >> > Sep 24 09:14:10 pgpool pgpool[12650]: [426-1] 2021-09-24
>> >> 09:14:10:
>> >> >> pid
>> >> >> >> >> > 12650: ERROR:  out of memory
>> >> >> >> >> > Sep 24 09:14:10 pgpool pgpool[12650]: [426-2] 2021-09-24
>> >> 09:14:10:
>> >> >> pid
>> >> >> >> >> > 12650: DETAIL:  Failed on request of size 33947648.
>> >> >> >> >> > Sep 24 09:14:10 pgpool pgpool[12650]: [426-3] 2021-09-24
>> >> 09:14:10:
>> >> >> pid
>> >> >> >> >> > 12650: LOCATION:  mcxt.c:900
>> >> >> >> >> >
>> >> >> >> >> > Here, two other ways we saw at the logs, but those just
>> occurred
>> >> >> once
>> >> >> >> >> each:
>> >> >> >> >> > Sep 24 07:33:14 pgpool pgpool[5874]: [434-1] 2021-09-24
>> >> 07:33:14:
>> >> >> pid
>> >> >> >> >> 5874:
>> >> >> >> >> > FATAL:  failed to fork a child
>> >> >> >> >> > Sep 24 07:33:14 pgpool pgpool[5874]: [434-2] 2021-09-24
>> >> 07:33:14:
>> >> >> pid
>> >> >> >> >> 5874:
>> >> >> >> >> > DETAIL:  system call fork() failed with reason: Cannot
>> allocate
>> >> >> memory
>> >> >> >> >> > Sep 24 07:33:14 pgpool pgpool[5874]: [434-3] 2021-09-24
>> >> 07:33:14:
>> >> >> pid
>> >> >> >> >> 5874:
>> >> >> >> >> > LOCATION:  pgpool_main.c:681
>> >> >> >> >> >
>> >> >> >> >> > And:
>> >> >> >> >> > Sep 23 17:07:40 pgpool kernel: [157160.691518] pgpool invoked
>> >> >> >> oom-killer:
>> >> >> >> >> > gfp_mask=0x24200ca, order=0, oom_score_adj=0
>> >> >> >> >> > Sep 23 17:07:40 pgpool kernel: [157160.691525] CPU: 1 PID:
>> 1194
>> >> >> Comm:
>> >> >> >> >> > pgpool Not tainted 4.4.276 #1
>> >> >> >> >> > Sep 23 17:07:40 pgpool kernel: [157160.691527] Hardware name:
>> >> >> VMware,
>> >> >> >> >> Inc.
>> >> >> >> >> > VMware Virtual Platform/440BX Desktop Reference Platform,
>> BIOS
>> >> 6.00
>> >> >> >> >> > 12/12/2018
>> >> >> >> >> > Sep 23 17:07:40 pgpool kernel: [157160.691528]
>> 0000000000000000
>> >> >> >> >> > ffff8803281cbae8 ffffffff81c930e7 ffff880420efe2c0
>> >> >> >> >> > Sep 23 17:07:40 pgpool kernel: [157160.691530]
>> ffff880420efe2c0
>> >> >> >> >> > ffff8803281cbb50 ffffffff81c8d9da ffff8803281cbb08
>> >> >> >> >> > Sep 23 17:07:40 pgpool kernel: [157160.691532]
>> ffffffff81133f1a
>> >> >> >> >> > ffff8803281cbb80 ffffffff81182eb0 ffff8800bba393c0
>> >> >> >> >> > Sep 23 17:07:40 pgpool kernel: [157160.691533] Call Trace:
>> >> >> >> >> > Sep 23 17:07:40 pgpool kernel: [157160.691540]
>> >> >> [<ffffffff81c930e7>]
>> >> >> >> >> > dump_stack+0x57/0x6d
>> >> >> >> >> > Sep 23 17:07:40 pgpool kernel: [157160.691542]
>> >> >> [<ffffffff81c8d9da>]
>> >> >> >> >> > dump_header.isra.9+0x54/0x1ae
>> >> >> >> >> > Sep 23 17:07:40 pgpool kernel: [157160.691547]
>> >> >> [<ffffffff81133f1a>] ?
>> >> >> >> >> > __delayacct_freepages_end+0x2a/0x30
>> >> >> >> >> > Sep 23 17:07:40 pgpool kernel: [157160.691553]
>> >> >> [<ffffffff81182eb0>] ?
>> >> >> >> >> > do_try_to_free_pages+0x350/0x3d0
>> >> >> >> >> > Sep 23 17:07:40 pgpool kernel: [157160.691556]
>> >> >> [<ffffffff811709f9>]
>> >> >> >> >> > oom_kill_process+0x209/0x3c0
>> >> >> >> >> > Sep 23 17:07:40 pgpool kernel: [157160.691558]
>> >> >> [<ffffffff81170eeb>]
>> >> >> >> >> > out_of_memory+0x2db/0x2f0
>> >> >> >> >> > Sep 23 17:07:40 pgpool kernel: [157160.691561]
>> >> >> [<ffffffff81176111>]
>> >> >> >> >> > __alloc_pages_nodemask+0xa81/0xae0
>> >> >> >> >> > Sep 23 17:07:40 pgpool kernel: [157160.691565]
>> >> >> [<ffffffff811ad2cd>]
>> >> >> >> >> > __read_swap_cache_async+0xdd/0x130
>> >> >> >> >> > Sep 23 17:07:40 pgpool kernel: [157160.691567]
>> >> >> [<ffffffff811ad337>]
>> >> >> >> >> > read_swap_cache_async+0x17/0x40
>> >> >> >> >> > Sep 23 17:07:40 pgpool kernel: [157160.691569]
>> >> >> [<ffffffff811ad455>]
>> >> >> >> >> > swapin_readahead+0xf5/0x190
>> >> >> >> >> > Sep 23 17:07:40 pgpool kernel: [157160.691571]
>> >> >> [<ffffffff8119ce3f>]
>> >> >> >> >> > handle_mm_fault+0xf3f/0x15e0
>> >> >> >> >> > Sep 23 17:07:40 pgpool kernel: [157160.691574]
>> >> >> [<ffffffff81c9d4e2>] ?
>> >> >> >> >> > __schedule+0x272/0x770
>> >> >> >> >> > Sep 23 17:07:40 pgpool kernel: [157160.691576]
>> >> >> [<ffffffff8104e241>]
>> >> >> >> >> > __do_page_fault+0x161/0x370
>> >> >> >> >> > Sep 23 17:07:40 pgpool kernel: [157160.691577]
>> >> >> [<ffffffff8104e49c>]
>> >> >> >> >> > do_page_fault+0xc/0x10
>> >> >> >> >> > Sep 23 17:07:40 pgpool kernel: [157160.691579]
>> >> >> [<ffffffff81ca3782>]
>> >> >> >> >> > page_fault+0x22/0x30
>> >> >> >> >> > Sep 23 17:07:40 pgpool kernel: [157160.691581] Mem-Info:
>> >> >> >> >> > Sep 23 17:07:40 pgpool kernel: [157160.691584]
>> >> active_anon:3564689
>> >> >> >> >> > inactive_anon:445592 isolated_anon:0
>> >> >> >> >> > Sep 23 17:07:40 pgpool kernel: [157160.691584]
>> active_file:462
>> >> >> >> >> > inactive_file:44 isolated_file:0
>> >> >> >> >> > Sep 23 17:07:40 pgpool kernel: [157160.691584]  unevictable:0
>> >> >> dirty:2
>> >> >> >> >> > writeback:2212 unstable:0
>> >> >> >> >> > Sep 23 17:07:40 pgpool kernel: [157160.691584]
>> >> >> slab_reclaimable:3433
>> >> >> >> >> > slab_unreclaimable:5859
>> >> >> >> >> > Sep 23 17:07:40 pgpool kernel: [157160.691584]  mapped:989
>> >> >> shmem:2607
>> >> >> >> >> > pagetables:16367 bounce:0
>> >> >> >> >> > Sep 23 17:07:40 pgpool kernel: [157160.691584]  free:51773
>> >> >> >> free_pcp:189
>> >> >> >> >> > free_cma:0
>> >> >> >> >> > Sep 23 17:07:40 pgpool kernel: [157160.691589] DMA
>> free:15904kB
>> >> >> >> min:128kB
>> >> >> >> >> > low:160kB high:192kB active_anon:0kB inactive_anon:0kB
>> >> >> active_file:0kB
>> >> >> >> >> > inactive_file:0kB unevictable:0kB isolated(anon):0kB
>> >> >> >> isolated(file):0kB
>> >> >> >> >> > present:15992kB managed:15904kB mlocked:0kB dirty:0kB
>> >> writeback:0kB
>> >> >> >> >> > mapped:0kB shmem:0kB slab_reclaimable:0kB
>> slab_unreclaimable:0kB
>> >> >> >> >> > kernel_stack:0kB pagetables:0kB unstable:0kB bounce:0kB
>> >> >> free_pcp:0kB
>> >> >> >> >> > local_pcp:0kB free_cma:0kB writeback_tmp:0kB pages_scanned:0
>> >> >> >> >> > all_unreclaimable? yes
>> >> >> >> >> > Sep 23 17:07:40 pgpool kernel: [157160.691590]
>> >> lowmem_reserve[]: 0
>> >> >> >> 2960
>> >> >> >> >> > 15991 15991
>> >> >> >> >> > Sep 23 17:07:40 pgpool kernel: [157160.691596] DMA32
>> >> free:77080kB
>> >> >> >> >> > min:25000kB low:31248kB high:37500kB active_anon:2352676kB
>> >> >> >> >> > inactive_anon:590536kB active_file:472kB inactive_file:140kB
>> >> >> >> >> > unevictable:0kB isolated(anon):0kB isolated(file):0kB
>> >> >> >> present:3129216kB
>> >> >> >> >> > managed:3043556kB mlocked:0kB dirty:0kB writeback:4144kB
>> >> >> mapped:1140kB
>> >> >> >> >> > shmem:3568kB slab_reclaimable:1028kB
>> slab_unreclaimable:3004kB
>> >> >> >> >> > kernel_stack:816kB pagetables:10988kB unstable:0kB bounce:0kB
>> >> >> >> >> > free_pcp:312kB local_pcp:196kB free_cma:0kB writeback_tmp:0kB
>> >> >> >> >> > pages_scanned:4292 all_unreclaimable? yes
>> >> >> >> >> > Sep 23 17:07:40 pgpool kernel: [157160.691597]
>> >> lowmem_reserve[]: 0
>> >> >> 0
>> >> >> >> >> 13031
>> >> >> >> >> > 13031
>> >> >> >> >> > Sep 23 17:07:40 pgpool kernel: [157160.691601] Normal
>> >> free:114108kB
>> >> >> >> >> > min:110032kB low:137540kB high:165048kB
>> active_anon:11906080kB
>> >> >> >> >> > inactive_anon:1191832kB active_file:1376kB inactive_file:36kB
>> >> >> >> >> > unevictable:0kB isolated(anon):0kB isolated(file):0kB
>> >> >> >> present:13631488kB
>> >> >> >> >> > managed:13343784kB mlocked:0kB dirty:8kB writeback:4704kB
>> >> >> >> mapped:2816kB
>> >> >> >> >> > shmem:6860kB slab_reclaimable:12704kB
>> slab_unreclaimable:20432kB
>> >> >> >> >> > kernel_stack:4848kB pagetables:54480kB unstable:0kB
>> bounce:0kB
>> >> >> >> >> > free_pcp:444kB local_pcp:196kB free_cma:0kB writeback_tmp:0kB
>> >> >> >> >> > pages_scanned:105664 all_unreclaimable? yes
>> >> >> >> >> > Sep 23 17:07:40 pgpool kernel: [157160.691602]
>> >> lowmem_reserve[]: 0
>> >> >> 0
>> >> >> >> 0 0
>> >> >> >> >> > Sep 23 17:07:40 pgpool kernel: [157160.691603] DMA: 0*4kB
>> 0*8kB
>> >> >> 0*16kB
>> >> >> >> >> > 1*32kB (U) 2*64kB (U) 1*128kB (U) 1*256kB (U) 0*512kB
>> 1*1024kB
>> >> (U)
>> >> >> >> >> 1*2048kB
>> >> >> >> >> > (U) 3*4096kB (M) = 15904kB
>> >> >> >> >> > Sep 23 17:07:40 pgpool kernel: [157160.691610] DMA32: 48*4kB
>> >> (ME)
>> >> >> >> 63*8kB
>> >> >> >> >> > (ME) 62*16kB (E) 46*32kB (UME) 35*64kB (UME) 26*128kB (UME)
>> >> >> 25*256kB
>> >> >> >> >> (UME)
>> >> >> >> >> > 61*512kB (UME) 28*1024kB (UME) 1*2048kB (M) 0*4096kB =
>> 77080kB
>> >> >> >> >> > Sep 23 17:07:40 pgpool kernel: [157160.691616] Normal:
>> 165*4kB
>> >> >> (MEH)
>> >> >> >> >> > 317*8kB (UMEH) 442*16kB (UMEH) 289*32kB (UMEH) 162*64kB
>> (UMEH)
>> >> >> >> 121*128kB
>> >> >> >> >> > (UMEH) 74*256kB (UMEH) 33*512kB (UMEH) 24*1024kB (ME)
>> 0*2048kB
>> >> >> >> 2*4096kB
>> >> >> >> >> (M)
>> >> >> >> >> > = 113980kB
>> >> >> >> >> > Sep 23 17:07:40 pgpool kernel: [157160.691623] 5552 total
>> >> pagecache
>> >> >> >> pages
>> >> >> >> >> > Sep 23 17:07:40 pgpool kernel: [157160.691624] 2355 pages in
>> >> swap
>> >> >> >> cache
>> >> >> >> >> > Sep 23 17:07:40 pgpool kernel: [157160.691625] Swap cache
>> stats:
>> >> >> add
>> >> >> >> >> > 5385308, delete 5382953, find 1159094/1325033
>> >> >> >> >> > Sep 23 17:07:40 pgpool kernel: [157160.691626] Free swap  =
>> 0kB
>> >> >> >> >> > Sep 23 17:07:40 pgpool kernel: [157160.691626] Total swap =
>> >> >> 4194300kB
>> >> >> >> >> > Sep 23 17:07:40 pgpool kernel: [157160.691627] 4194174 pages
>> RAM
>> >> >> >> >> > Sep 23 17:07:40 pgpool kernel: [157160.691628] 0 pages
>> >> >> >> >> HighMem/MovableOnly
>> >> >> >> >> > Sep 23 17:07:40 pgpool kernel: [157160.691628] 93363 pages
>> >> reserved
>> >> >> >> >> > Sep 23 17:07:40 pgpool kernel: [157160.691989] Out of memory:
>> >> Kill
>> >> >> >> >> process
>> >> >> >> >> > 8975 (pgpool) score 7 or sacrifice child
>> >> >> >> >> > Sep 23 17:07:40 pgpool kernel: [157160.691995] Killed process
>> >> 8975
>> >> >> >> >> (pgpool)
>> >> >> >> >> > total-vm:337504kB, anon-rss:166824kB, file-rss:1920kB
>> >> >> >> >> >
>> >> >> >> >> >
>> >> >> >> >> >
>> >> >> >> >> > On Mon, Sep 27, 2021 at 1:22 AM Tatsuo Ishii <
>> >> ishii at sraoss.co.jp>
>> >> >> >> wrote:
>> >> >> >> >> >
>> >> >> >> >> >> Hi,
>> >> >> >> >> >>
>> >> >> >> >> >> > Hello,
>> >> >> >> >> >> >
>> >> >> >> >> >> > Our pgpool is consuming A LOT of memory and frequently
>> dies
>> >> >> with:
>> >> >> >> Out
>> >> >> >> >> of
>> >> >> >> >> >> > memory error.
>> >> >> >> >> >> >
>> >> >> >> >> >> > We have 2 backends, 1 master and 1 slave. Here some
>> config:
>> >> >> >> >> >> > num_init_children = 150
>> >> >> >> >> >> > max_pool = 1
>> >> >> >> >> >> > child_life_time = 300
>> >> >> >> >> >> > child_max_connections = 1
>> >> >> >> >> >> > connection_life_time = 0
>> >> >> >> >> >> > client_idle_limit = 0
>> >> >> >> >> >> > connection_cache = on
>> >> >> >> >> >> > load_balance_mode = on
>> >> >> >> >> >> > memory_cache_enabled = off
>> >> >> >> >> >> >
>> >> >> >> >> >> > RAM: 16Gb
>> >> >> >> >> >> >
>> >> >> >> >> >> > Does anyone have a clue what's going on?
>> >> >> >> >> >> >
>> >> >> >> >> >> > Thank you.
>> >> >> >> >> >>
>> >> >> >> >> >> Is that OOM killer or pgpool itself aborted with an out of
>> >> memory
>> >> >> >> >> >> error?  If latter, can you share the pgpool log?
>> >> >> >> >> >> --
>> >> >> >> >> >> Tatsuo Ishii
>> >> >> >> >> >> SRA OSS, Inc. Japan
>> >> >> >> >> >> English: http://www.sraoss.co.jp/index_en.php
>> >> >> >> >> >> Japanese:http://www.sraoss.co.jp
>> >> >> >> >> >>
>> >> >> >> >> >
>> >> >> >> >> >
>> >> >> >> >> > --
>> >> >> >> >> > Luiz Fernando Pasqual S. Souza
>> >> >> >> >> > mail: luiz at pasquall.com
>> >> >> >> >>
>> >> >> >> >
>> >> >> >> >
>> >> >> >> > --
>> >> >> >> > Luiz Fernando Pasqual S. Souza
>> >> >> >> > mail: luiz at pasquall.com
>> >> >> >>
>> >> >> >
>> >> >> >
>> >> >> > --
>> >> >> > Luiz Fernando Pasqual S. Souza
>> >> >> > mail: luiz at pasquall.com
>> >> >>
>> >> >
>> >> >
>> >> > --
>> >> > Luiz Fernando Pasqual S. Souza
>> >> > mail: luiz at pasquall.com
>> >> _______________________________________________
>> >> pgpool-general mailing list
>> >> pgpool-general at pgpool.net
>> >> http://www.pgpool.net/mailman/listinfo/pgpool-general
>> >>
>> >
>> >
>> > --
>> > Luiz Fernando Pasqual S. Souza
>> > mail: luiz at pasquall.com
>>
> 
> 
> -- 
> Luiz Fernando Pasqual S. Souza
> mail: luiz at pasquall.com


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