View Issue Details

IDProjectCategoryView StatusLast Update
0000524Pgpool-IIBugpublic2019-08-13 16:47
ReportervanAssigned Tot-ishii 
PriorityhighSeverityminorReproducibilityalways
Status feedbackResolutionopen 
Product Version4.0.2 
Target VersionFixed in Version 
Summary0000524: pgpool performance issue
DescriptionHi ,

connect call to pgppool is taking too much time (approx 200- 300 millisecond ) even though lots of pgpool child are free to accept a new connection .


OS:freebsd
Version: 4.0.2


PS: we didn't find system requirement for pgpool anywhere, can it be because of low ram or cpu?

Attaching the pgpool.conf file
 
TagsNo tags attached.

Activities

van

2019-06-25 03:24

reporter  

pgpool.conf (40,156 bytes)

t-ishii

2019-06-25 15:18

developer   ~0002675

Taking 200ms to connect to Pgpool-II is unusual. Can you do a test something like this:

1. set num_init_children to 1.
2. See if the connect time gets shorter. If so, it is likely that your hardware is not good enough to support num_init_children = 300. Upgrade the hardware or reduce num_init_children.
3. If still it takes 200ms, attach system call trace tool to pgpool child process (you can find by using ps. Look for something like "pgpool: wait for connection request").
4. Send the output of system call trace tool. BTW, I am not familiar with FreeBSD. When I say "system call trace tool", I mean something like strace in Linux.

van

2019-06-25 18:37

reporter   ~0002677

Hi t-ishii,

With 1, connect time is shorter .
Ideally how much CPU and RAM is required for pgpool (with 300 num_init_children) ?
my system has 4 GB ram and 4 virtual CPU .

t-ishii

2019-06-26 10:56

developer   ~0002680

You might want to try serialize_accept = on. This reduces the process awaking overhead when num_init_children is large.

BTW, to know if CPU or RAM are sufficient, you can use vmstat or same tools.

t-ishii

2019-08-13 16:47

developer   ~0002775

No response from the reporter over 1 month. Issue will be closed soon.

Issue History

Date Modified Username Field Change
2019-06-25 03:24 van New Issue
2019-06-25 03:24 van File Added: pgpool.conf
2019-06-25 15:08 t-ishii Assigned To => t-ishii
2019-06-25 15:08 t-ishii Status new => assigned
2019-06-25 15:18 t-ishii Note Added: 0002675
2019-06-25 15:18 t-ishii Status assigned => feedback
2019-06-25 15:18 t-ishii Description Updated View Revisions
2019-06-25 18:37 van Note Added: 0002677
2019-06-25 18:37 van Status feedback => assigned
2019-06-26 10:56 t-ishii Note Added: 0002680
2019-06-26 10:56 t-ishii Status assigned => feedback
2019-08-13 16:47 t-ishii Note Added: 0002775