From: Tony Liao <tonyliao@yuehetone.com>
To: pgsql-admin@postgresql.org
Subject: multi-threading access problem
Date: Fri, 6 Mar 2009 19:43:50 +0800
Message-ID: <8f750b7c0903060343l60cf0870rb7e421abcda63d6e@mail.gmail.com> (raw)
hello,everyone.
I have a c test-program for "select query",if the program create
thread every 3ms,it runs smoothly.but when the duration time interval reduce
to 2.8ms,the sleeping process increase more and more,and then the server
crash.the cpu and memory used percentage under 50%.
my postgresql.conf file as bellow:
max_connections = 5000
shared_buffers = 1000MB
work_mem = 256MB
maintenance_work_mem = 512MB
max_stack_depth = 10MB
max_fsm_pages = 204800
max_fsm_relations = 1000
checkpoint_segments = 5
checkpoint_timeout = 5min
checkpoint_completion_target = 0.5
checkpoint_warning = 30s
enable_seqscan = off
seq_page_cost = 10.0 # measured on an arbitrary scale
random_page_cost = 20.0 # same scale as above
cpu_tuple_cost = 1.0 # same scale as above
cpu_index_tuple_cost = 0.4 # same scale as above
cpu_operator_cost = 0.2 # same scale as above
effective_cache_size = 128MB
geqo = on
geqo_threshold = 11
geqo_effort = 6
default_statistics_target = 250
from_collapse_limit = 16
join_collapse_limit = 16
datestyle = 'iso, mdy'
lc_messages = 'en_US.UTF-8'
lc_monetary = 'en_US.UTF-8' # locale for monetary formatting
lc_numeric = 'en_US.UTF-8' # locale for number formatting
lc_time = 'en_US.UTF-8'
default_text_search_config = 'pg_catalog.english'
deadlock_timeout = 1s
max_locks_per_transaction = 96
server hardware : double cpu xeon 5405,4G memory.the table of database have
2millions records.
Maybe I should adjust system performance,but how? anyone can help me?
thanks.
Tony Liao
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-admin@postgresql.org
Cc: tonyliao@yuehetone.com
Subject: Re: multi-threading access problem
In-Reply-To: <8f750b7c0903060343l60cf0870rb7e421abcda63d6e@mail.gmail.com>
* 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