Обсуждение: Re: Re: patch submission: truncate trailing nulls from heap rows to reduce the size of the null bitmap [Review]

On Wednesday, January 23, 2013 2:30 AM Jameison Martin wrote:

> Sorry for the late response, I just happened to see this yesterday.

> Running a general benchmark against the patch as Keven suggests is a good
idea. 

> Amit, can you supply the actual values you saw when running pgbench (the 3
values for each run)?
 I haven't saved that, but I have plan to run it once again as Simon also
pointed it.

> I'd like to verify
> that the 1% difference isn't due to some file system/OS variability (would
be interested in what the stdev is for the
> values). Also, do you happen to have some information about the hardware
you ran on?

Platform details:   Operating System: Suse-Linux 10.2 x86_64   Hardware : 4 core (Intel(R) Xeon(R) CPU L5408 @ 2.13GHz)
 RAM : 24GB 

> Meanwhile, I'll rerun on my end to see if I can reproduce your numbers.
And I'll get a run of pgbench with minimal I/O > since that can induce a lot
of variability.

> Also, Amit, I want to thank you for all your work on this patch, it is
greatly appreciated.
 As a Reviewer, I tried my best for this patch.


On Monday, December 24, 2012 7:58 PM Kevin Grittner wrote:
Simon Riggs wrote:

Not really sure about the 100s of columns use case.

But showing gain in useful places in these more common cases wins
my vote.

Thanks for testing. Barring objections, will commit.
Do we have any results on just a plain, old stock pgbench run, with
the default table definitions?

That would be a reassuring complement to the other tests.
Sever Configuration:
The database cluster will be initialized with locales  COLLATE:  C  CTYPE:    C  MESSAGES: en_US.UTF-8  MONETARY:
en_US.UTF-8 NUMERIC:  en_US.UTF-8  TIME:     en_US.UTF-8  

shared_buffers = 1GB
checkpoint_segments = 255
checkpoint_timeout = 15min

pgbench:
transaction type: TPC-B (sort of)
scaling factor: 75
query mode: simple
number of clients: 8
number of threads: 8
duration: 600 s

Performance: Average of 3 runs of pgbench in tps
9.3devel  |  with trailing null patch
----------+--------------------------
578.9872  |   573.4980

With Regards,
Amit Kapila.

On Wednesday, January 23, 2013 2:30 AM Jameison Martin wrote:

> Sorry for the late response, I just happened to see this yesterday.

> Running a general benchmark against the patch as Keven suggests is a good
idea. 

> Amit, can you supply the actual values you saw when running pgbench (the 3
values for each run)? I'd like to verify
> that the 1% difference isn't due to some file system/OS variability (would
be interested in what the stdev is for the
> values). Also, do you happen to have some information about the hardware
you ran on?

Performance data for 5 runs is as below:

System Configuration:
Hardware : 4 core (Intel(R) Xeon(R) CPU L5408 @ 2.13GHz) &  RAM : 24GB
Operating System: Suse-Linux 10.2 x86_64

Sever Configuration:
The database cluster will be initialized with locales  COLLATE:  C  CTYPE:    C  MESSAGES: en_US.UTF-8  MONETARY:
en_US.UTF-8 NUMERIC:  en_US.UTF-8  TIME:     en_US.UTF-8  

shared_buffers = 2GB
checkpoint_segments = 255
checkpoint_timeout = 10min

pgbench:
transaction type: TPC-B (sort of)
scaling factor: 75
query mode: simple
number of clients: 8
number of threads: 8
duration: 300 s
        original        patch Run-1: 579.596730    570.212601 Run-2: 577.220325    576.719402 Run-3: 571.792736
574.118542Run-4: 573.376879    571.548136 Run-5: 573.469166    576.321368  Avg  : 575.091167    573.784009 


With Regards,
Amit Kapila.

On Monday, December 24, 2012 7:58 PM Kevin Grittner wrote:
Simon Riggs wrote:

Not really sure about the 100s of columns use case.

But showing gain in useful places in these more common cases wins
my vote.

Thanks for testing. Barring objections, will commit.
Do we have any results on just a plain, old stock pgbench run, with
the default table definitions?

That would be a reassuring complement to the other tests.
Sever Configuration:
The database cluster will be initialized with locales  COLLATE:  C  CTYPE:    C  MESSAGES: en_US.UTF-8  MONETARY:
en_US.UTF-8 NUMERIC:  en_US.UTF-8  TIME:     en_US.UTF-8  

shared_buffers = 1GB
checkpoint_segments = 255
checkpoint_timeout = 15min

pgbench:
transaction type: TPC-B (sort of)
scaling factor: 75
query mode: simple
number of clients: 8
number of threads: 8
duration: 600 s

Performance: Average of 3 runs of pgbench in tps
9.3devel  |  with trailing null patch
----------+--------------------------
578.9872  |   573.4980

With Regards,
Amit Kapila.