Обсуждение: Quad Xeon or Quad Opteron?

Hello,

 We're planning new production server for PostgreSQL and I'm wondering
which processor (or even platform) will be better: Quad Xeon or Quad
Opteron (for example SUN now has a new offer Sun Fire X4440 x64).

When I was buying my last database server, then SUN v40z was a really
very good choice (Intel's base server was slower). This v40z still works
pretty good but I need one more.

AFAIK Intel made some changes in chipset but... is this better then AMD
HyperTransport and Direct Connect Architecture from database point of
view? How about L3 cache - is this important for performance?

Do You have any opinions? Suggestions?

Thanks,

Best regards

--
Andrzej Zawadzki

Andrzej Zawadzki wrote:
> Hello,
>
>  We're planning new production server for PostgreSQL and I'm wondering
> which processor (or even platform) will be better: Quad Xeon or Quad
> Opteron (for example SUN now has a new offer Sun Fire X4440 x64).

[snip]

> Suggestions?

To get a more useful response here, you might want to include some
information about your workload and database size, and report on your
planned disk subsystem and RAM.

Also, based on what I've seen on this list rather than personal
experience, you might want to give more thought to your storage than to
CPU power. The usual thrust of advice seems to be: Get a fast, battery
backed RAID controller. "Fast" does not mean "fast sequential I/O in
ideal conditions so marketing can print a big number on the box"; you
need to consider random I/O too. Get lots of fast disks. Get enough RAM
to ensure that your indexes fit in RAM if possible.

Note, however, that I have no direct experience with big Pg databases;
I'm just trying to provide you with a guide of what information to
provide and what to think about so you can get better answers here from
people who actually have a clue.

--
Craig Ringer

> Also, based on what I've seen on this list rather than personal
> experience, you might want to give more thought to your storage than to
> CPU power. The usual thrust of advice seems to be: Get a fast, battery
> backed RAID controller. "Fast" does not mean "fast sequential I/O in
> ideal conditions so marketing can print a big number on the box"; you
> need to consider random I/O too. Get lots of fast disks. Get enough RAM
> to ensure that your indexes fit in RAM if possible.
> Note, however, that I have no direct experience with big Pg databases;
> I'm just trying to provide you with a guide of what information to
> provide and what to think about so you can get better answers here from
> people who actually have a clue.

Yep,  we've had PostreSQL databases for a long time.  The various
current generation processors, IMO, have no substantive difference in
practice;  at least not relative to the bang-for-the-buck or more RAM
and good I/O.

Hi,
As a gauge, we recently purchased several servers as our systems get
close to going operational. We bought Dell 2900s, with the cheapest quad
core processors (dual) and put most of the expense into lots of drives
(8 15K 146GB SAS drives in a RAID 10 set), and the PERC 6 embedded
controller with 512MB battery backed cache. That gives us more spindles,
the RAID redundancy we want, plus the high, reliable throughput of the
BBC. The OS (and probably WAL) will run on a RAID 1 pair of 15K 76GB
drives. We also went with 8GB memory, which seemed to be the price cost
point in these systems (going above 8GB had a much higher cost).
Besides, in our prototyping, or systems had 2GB, which we rarely
exceeded, so 8GB should be plently (and we can always expand).

So really, if you can save money on processors by going Opteron (and
your IT department doesn't have an Intel-based system requirement like
ours), put what you save into a good disk I/O subsystem. Hope that
helps.

Doug

-----Original Message-----
From: pgsql-performance-owner@postgresql.org
[mailto:pgsql-performance-owner@postgresql.org] On Behalf Of Adam Tauno
Williams
Sent: Friday, May 23, 2008 8:22 AM
To: pgsql-performance
Subject: Re: [PERFORM] Quad Xeon or Quad Opteron?

> Also, based on what I've seen on this list rather than personal
> experience, you might want to give more thought to your storage than
to
> CPU power. The usual thrust of advice seems to be: Get a fast, battery
> backed RAID controller. "Fast" does not mean "fast sequential I/O in
> ideal conditions so marketing can print a big number on the box"; you
> need to consider random I/O too. Get lots of fast disks. Get enough
RAM
> to ensure that your indexes fit in RAM if possible.
> Note, however, that I have no direct experience with big Pg databases;
> I'm just trying to provide you with a guide of what information to
> provide and what to think about so you can get better answers here
from
> people who actually have a clue.

Yep,  we've had PostreSQL databases for a long time.  The various
current generation processors, IMO, have no substantive difference in
practice;  at least not relative to the bang-for-the-buck or more RAM
and good I/O.


--
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To make changes to your subscription:
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This may be of interest...


http://weblog.infoworld.com/yager/archives/2008/05/ahead_of_the_cu_4.html

-----Original Message-----
From: pgsql-performance-owner@postgresql.org on behalf of Andrzej Zawadzki
Sent: Fri 5/23/2008 6:41 AM
To: pgsql-performance@postgresql.org
Subject: [PERFORM] Quad Xeon or Quad Opteron?

Hello,

 We're planning new production server for PostgreSQL and I'm wondering
which processor (or even platform) will be better: Quad Xeon or Quad
Opteron (for example SUN now has a new offer Sun Fire X4440 x64).

When I was buying my last database server, then SUN v40z was a really
very good choice (Intel's base server was slower). This v40z still works
pretty good but I need one more.

AFAIK Intel made some changes in chipset but... is this better then AMD
HyperTransport and Direct Connect Architecture from database point of
view? How about L3 cache - is this important for performance?

Do You have any opinions? Suggestions?

Thanks,

Best regards

--
Andrzej Zawadzki

--
Sent via pgsql-performance mailing list (pgsql-performance@postgresql.org)
To make changes to your subscription:
http://www.postgresql.org/mailpref/pgsql-performance

Craig Ringer wrote:
> Andrzej Zawadzki wrote:
>
>> Hello,
>>
>>  We're planning new production server for PostgreSQL and I'm wondering
>> which processor (or even platform) will be better: Quad Xeon or Quad
>> Opteron (for example SUN now has a new offer Sun Fire X4440 x64).
>>
>
> [snip]
>
>
>> Suggestions?
>>
>
> To get a more useful response here, you might want to include some
> information about your workload and database size, and report on your
> planned disk subsystem and RAM.
>
Disk subsystem:
Hitachi AMS200, 12x10krpm SAS drives in RAID 10 (+1 hot spare), 1GB mem
with battery
Database is ~60GB and growing ;-)
Workloads: ~94% - SELECTS
Q/sek: Avg~300 (1000 in peak)

Server:
v40z is a 4xdouble core with 16GB RAM

> Also, based on what I've seen on this list rather than personal
> experience, you might want to give more thought to your storage than to
> CPU power. The usual thrust of advice seems to be: Get a fast, battery
> backed RAID controller. "Fast" does not mean "fast sequential I/O in
> ideal conditions so marketing can print a big number on the box"; you
> need to consider random I/O too. Get lots of fast disks. Get enough RAM
> to ensure that your indexes fit in RAM if possible.
>
Yes, of course You are right: disks are very important - I know that
especially after switch to SAN.
But server is getting older ;-) - I need good warranty - I have 3 years
from SUN for example.

ps. After reading about HP: SA P800 with StorageWorks MSA70 I'm
considering buying such storage with ~20 disks.

[...]

--
Andrzej Zawadzki

Knight, Doug wrote:
> Hi,
> As a gauge, we recently purchased several servers as our systems get
> close to going operational. We bought Dell 2900s, with the cheapest quad
> core processors (dual) and put most of the expense into lots of drives
> (8 15K 146GB SAS drives in a RAID 10 set), and the PERC 6 embedded
> controller with 512MB battery backed cache. That gives us more spindles,
> the RAID redundancy we want, plus the high, reliable throughput of the
> BBC. The OS (and probably WAL) will run on a RAID 1 pair of 15K 76GB
> drives. We also went with 8GB memory, which seemed to be the price cost
> point in these systems (going above 8GB had a much higher cost).
> Besides, in our prototyping, or systems had 2GB, which we rarely
> exceeded, so 8GB should be plently (and we can always expand).
>
> So really, if you can save money on processors by going Opteron (and
> your IT department doesn't have an Intel-based system requirement like
> ours), put what you save into a good disk I/O subsystem. Hope that
> helps.
>
Top posting? Bleee ;-) How to read now?

OK I know that IO is most important for database but: I'm sorry, my
question is about processor/platform choice? :-)
I have to buy new server and I want optimal one.
Like I've wrote in different email my IO subsystem is quite good for now.

ps. To admin of that list: what is with Reply-to on that list?



> Doug
>
> -----Original Message-----
> From: pgsql-performance-owner@postgresql.org
> [mailto:pgsql-performance-owner@postgresql.org] On Behalf Of Adam Tauno
> Williams
> Sent: Friday, May 23, 2008 8:22 AM
> To: pgsql-performance
> Subject: Re: [PERFORM] Quad Xeon or Quad Opteron?
>
>
>> Also, based on what I've seen on this list rather than personal
>> experience, you might want to give more thought to your storage than
>>
> to
>
>> CPU power. The usual thrust of advice seems to be: Get a fast, battery
>> backed RAID controller. "Fast" does not mean "fast sequential I/O in
>> ideal conditions so marketing can print a big number on the box"; you
>> need to consider random I/O too. Get lots of fast disks. Get enough
>>
> RAM
>
>> to ensure that your indexes fit in RAM if possible.
>> Note, however, that I have no direct experience with big Pg databases;
>> I'm just trying to provide you with a guide of what information to
>> provide and what to think about so you can get better answers here
>>
> from
>
>> people who actually have a clue.
>>
>
> Yep,  we've had PostreSQL databases for a long time.  The various
> current generation processors, IMO, have no substantive difference in
> practice;  at least not relative to the bang-for-the-buck or more RAM
> and good I/O.
>
>
>