Thread: PostgreSQL Article on tucows

PostgreSQL Article on tucows

From
Justin Clift
Date:
Hi all,

Branden has written an "Introduction to PostgreSQL" article for the
Tucows network (another high profile group of sites):

http://news.tucows.com/
http://news.tucows.com/linux/40605.html

:-)

Regards and best wishes,

Justin Clift

--
"My grandfather once told me that there are two kinds of people: those
who work and those who take the credit. He told me to try to be in the
first group; there was less competition there."
   - Indira Gandhi

Sparc seems very slow

From
"Tille, Andreas"
Date:
Hello,

I´ve got a Sparc E250 server and I´m runing Debian GNU/Linux on it.
I now started to make some performance comparisons against a default PC.
Here are the configurations I used:

E250:
  ~> cat /proc/cpuinfo
  cpu             : TI UltraSparc II  (BlackBird)
  fpu             : UltraSparc II integrated FPU
  promlib         : Version 3 Revision 16
  prom            : 3.16.1
  type            : sun4u
  ncpus probed    : 2
  ncpus active    : 2
  Cpu0Bogo        : 799.53
  Cpu1Bogo        : 799.53
  MMU Type        : Spitfire
  State:
  CPU0:           online
  CPU1:           online

  2 GB RAM
  4x36 GB SCSI

  ~> uname -a
  Linux bse 2.2.18pre21 #1 SMP Tue Dec 19 22:53:19 CET 2000 sparc64 unknown

  ~> dpkg --status postgresql
  Package: postgresql
  Maintainer: Oliver Elphick <Oliver.Elphick@lfix.co.uk>
  Version: 7.1.2-4


PC:
  ~> cat /proc/cpuinfo
  processor       : 0
  vendor_id       : GenuineIntel
  cpu family      : 6
  model           : 8
  model name      : Pentium III (Coppermine)
  stepping        : 6
  cpu MHz         : 795.576
  cache size      : 256 KB
  fpu             : yes
  fpu_exception   : yes
  cpuid level     : 2
  wp              : yes
  flags           : fpu vme de pse tsc msr pae mce cx8 sep mtrr pge mca cmov pat pse36 mmx fxsr sse
  bogomips        : 1589.24

  256 MB RAM
  20 GB IDE

  ~> uname -a
  Linux wr-linux02 2.4.5 #1 Mit Mai 30 08:24:06 CEST 2001 i686 unknown

  ~> dpkg --status postgresql
  Package: postgresql
  Maintainer: Oliver Elphick <Oliver.Elphick@lfix.co.uk>
  Version: 7.1.2-1

At first I created a set of tables and indexes using

   ~> date; cat ifsg.pgsql | psql ifsg; date

where
   ~> grep "CREATE *TABLE" ifsg.pgsql | wc -l
     40
   ~> grep "CREATE *INDEX" ifsg.pgsql | wc -l
    117

E250:
  Fre Aug 17 13:40:03 CEST 2001
  Fre Aug 17 13:40:14 CEST 2001

PC:
  Don Aug 16 14:15:24 CEST 2001
  Don Aug 16 14:15:28 CEST 2001

so the PC is about more 2 times faster. (By the way postgresql 7.0.2 took
24 seconds on this machine for this job.)
Next I started inserting some amount of data:

  ~> ls -l T000001_010000.TXT
  -rw-r--r--    1 tillea   admin    19196240 15. Aug 13:42 T000001_010000.TXT
  ~>  grep -i "INSERT" T000001_010000.TXT |  wc -l
  63481
  ~>  date; cat T000001_010000.TXT | psql ifsg; date

E250:
  Fre Aug 17 13:41:42 CEST 2001
  Fre Aug 17 13:57:52 CEST 2001
(version 7.0.2 took 1 hour for this task)

PC:
  Don Aug 16 15:23:34 CEST 2001
  Don Aug 16 15:24:51 CEST 2001

The question is:  Is there any reason for the fact that the PC is nearly ten
times faster for the same task?  By the way, I´m using identical
/etc/postgresql/pg_hba.conf and /etc/postgresql/postgresql.conf for both
boxes.

The only difference I can see are different Linux kernel versions (perhaps
2.4 series has better drivers to speed up disk access) but I wanted to
stay tuned before upgrading to 2.4 for production machines.  Has anybody
experiences using Solaris in a comparable machine?

Kind regards

          Andreas.

Re: Sparc seems very slow

From
Rocke Robertson
Date:

"Tille, Andreas" wrote:

> Hello,
>
> I´ve got a Sparc E250 server and I´m runing Debian GNU/Linux on it.
> I now started to make some performance comparisons against a default PC.
> Here are the configurations I used:
>

I run PostGress on Solaris 7 on an E450 and it works just great.  2x300MHz and 1 GB or memory. I am
using the native logging ufs filesystems. It would probably run quicker if I used VxFS....

If your E250 is that much slower... I would look at all the usual bottlenecks. First start off with
SCSI error messages. If it is that slow, your bus must be slowed down for some reason. Is it I/O
bound.... What kind of throughput are you getting to your disks. Use iostat or Linux's equivalent. If
it is really quite slow compared to what you can do with just a dd writing to a disk, then you have a
problem with the way that postgresql was built, not your disk. Also look at .... Memory..... User cpu
time and System cpu time ....etc.. If memory serves me correctly, Linux has a feature that allows you
to trace system calls (Like any good unix and unix like O/S should) I would recommend having a look at
that...strace ?

If all else fails....install Solaris 7/8. (Subject to discretion of course).

Hope this helps.



>
> E250:
>   ~> cat /proc/cpuinfo
>   cpu             : TI UltraSparc II  (BlackBird)
>   fpu             : UltraSparc II integrated FPU
>   promlib         : Version 3 Revision 16
>   prom            : 3.16.1
>   type            : sun4u
>   ncpus probed    : 2
>   ncpus active    : 2
>   Cpu0Bogo        : 799.53
>   Cpu1Bogo        : 799.53
>   MMU Type        : Spitfire
>   State:
>   CPU0:           online
>   CPU1:           online
>
>   2 GB RAM
>   4x36 GB SCSI
>
>   ~> uname -a
>   Linux bse 2.2.18pre21 #1 SMP Tue Dec 19 22:53:19 CET 2000 sparc64 unknown
>
>   ~> dpkg --status postgresql
>   Package: postgresql
>   Maintainer: Oliver Elphick <Oliver.Elphick@lfix.co.uk>
>   Version: 7.1.2-4
>
> PC:
>   ~> cat /proc/cpuinfo
>   processor       : 0
>   vendor_id       : GenuineIntel
>   cpu family      : 6
>   model           : 8
>   model name      : Pentium III (Coppermine)
>   stepping        : 6
>   cpu MHz         : 795.576
>   cache size      : 256 KB
>   fpu             : yes
>   fpu_exception   : yes
>   cpuid level     : 2
>   wp              : yes
>   flags           : fpu vme de pse tsc msr pae mce cx8 sep mtrr pge mca cmov pat pse36 mmx fxsr sse
>   bogomips        : 1589.24
>
>   256 MB RAM
>   20 GB IDE
>
>   ~> uname -a
>   Linux wr-linux02 2.4.5 #1 Mit Mai 30 08:24:06 CEST 2001 i686 unknown
>
>   ~> dpkg --status postgresql
>   Package: postgresql
>   Maintainer: Oliver Elphick <Oliver.Elphick@lfix.co.uk>
>   Version: 7.1.2-1
>
> At first I created a set of tables and indexes using
>
>    ~> date; cat ifsg.pgsql | psql ifsg; date
>
> where
>    ~> grep "CREATE *TABLE" ifsg.pgsql | wc -l
>      40
>    ~> grep "CREATE *INDEX" ifsg.pgsql | wc -l
>     117
>
> E250:
>   Fre Aug 17 13:40:03 CEST 2001
>   Fre Aug 17 13:40:14 CEST 2001
>
> PC:
>   Don Aug 16 14:15:24 CEST 2001
>   Don Aug 16 14:15:28 CEST 2001
>
> so the PC is about more 2 times faster. (By the way postgresql 7.0.2 took
> 24 seconds on this machine for this job.)
> Next I started inserting some amount of data:
>
>   ~> ls -l T000001_010000.TXT
>   -rw-r--r--    1 tillea   admin    19196240 15. Aug 13:42 T000001_010000.TXT
>   ~>  grep -i "INSERT" T000001_010000.TXT |  wc -l
>   63481
>   ~>  date; cat T000001_010000.TXT | psql ifsg; date
>
> E250:
>   Fre Aug 17 13:41:42 CEST 2001
>   Fre Aug 17 13:57:52 CEST 2001
> (version 7.0.2 took 1 hour for this task)
>
> PC:
>   Don Aug 16 15:23:34 CEST 2001
>   Don Aug 16 15:24:51 CEST 2001
>
> The question is:  Is there any reason for the fact that the PC is nearly ten
> times faster for the same task?  By the way, I´m using identical
> /etc/postgresql/pg_hba.conf and /etc/postgresql/postgresql.conf for both
> boxes.
>
> The only difference I can see are different Linux kernel versions (perhaps
> 2.4 series has better drivers to speed up disk access) but I wanted to
> stay tuned before upgrading to 2.4 for production machines.  Has anybody
> experiences using Solaris in a comparable machine?
>
> Kind regards
>
>           Andreas.
>
> ---------------------------(end of broadcast)---------------------------
> TIP 4: Don't 'kill -9' the postmaster

--
Rocke Robertson
NCS/GTIS/PWGSC
700 Montreal Rd.
Rocker@tiger.pwgsc.gc.ca
(613) 748-4604



Re: Sparc seems very slow

From
"Colin 't Hart"
Date:
> I�ve got a Sparc E250 server and I�m runing Debian GNU/Linux on it.
> I now started to make some performance comparisons against a default PC.

What's the performance like under Solaris 2.6?


(Yes I know Solaris 2.6 is old, but 80% of Sun's customers still have
Solaris 2.6 systems... although this doesn't mean that 80% of all Sun
hardware still runs Solaris 2.6)


Cheers,

Colin