Re: [PERFORM] Capacitors, etc., in hard drives and SSD for DBMS machines...

On 07/08/2016 07:44 AM, vincent wrote: > > > Op 7/8/2016 om 12:23 PM schreef Jean-David Beyer: >> Why all this concern about how long a disk (or SSD) drive can stay up >> after a power failure? >> >> It seems to me that anyone interested in maintaining an

[PERFORM] Capacitors, etc., in hard drives and SSD for DBMS machines...

seconds, my natural gas fueled backup generator picks up the load very quickly. Am I overlooking something? -- .~. Jean-David Beyer Registered Linux User 85642. /V\ PGP-Key:166D840A 0C610C8B Registered Machine 1935521. /( )\ Shrewsbury, New Jerseyhttp://linuxcounter.net

Re: [PERFORM] Postgres is using 100% CPU

rows at once, you are doing it as 273 transactions instead of one? -- .~. Jean-David Beyer Registered Linux User 85642. /V\ PGP-Key:166D840A 0C610C8B Registered Machine 1935521. /( )\ Shrewsbury, New Jerseyhttp://linuxcounter.net ^^-^^ 09:00:01 up 3 days, 9:57, 2 users, load

Re: [PERFORM] hardware upgrade, performance degrade?

On 03/03/2013 03:16 PM, Josh Berkus wrote: Steven, We saw the same performance problems when this new hardware was running cent 6.3 with a 2.6.32-279.19.1.el6.x86_64 kernel and when it was matched to the OS/kernel of the old hardware which was cent 5.8 with a 2.6.18-308.11.1.el5 kernel.

Re: xfs perform a lot better than ext4 [WAS: Re: [PERFORM] Two identical systems, radically different performance]

On 12/05/2012 10:34 AM, Andrea Suisani wrote: [sorry for resuming an old thread] [cut] Question is... will that remove the performance penalty of HyperThreading? So I've added to my todo list to perform a test to verify this claim :) done. on this box: in a brief: the box is dell a

Re: [PERFORM] Best suiting OS

find that for some tasks involving global editing, that vi is a lot easier to use. But for most of the things I do on a regular basis, if find emacs better. So, for me, it is not which is the better editor, but which is the better editor for the task at hand. -- .~. Jean-David Beyer

Re: [PERFORM] Best suiting OS

Linux 5, since they do not add any new features and only correct errors. CentOS is the same as Red Hat, but you probably get better support from Red Hat if you need it -- though you pay for it. -- .~. Jean-David Beyer Registered Linux User 85642. /V\ PGP-Key: 9A2FC99A

Re: [PERFORM] Best suiting OS

, with Red Hat, you will need to upgrade to a whole new distribution whenever you want updated software, which is a much bigger undertaking. -- .~. Jean-David Beyer Registered Linux User 85642. /V\ PGP-Key: 9A2FC99A Registered Machine 241939. /( )\ Shrewsbury, New Jersey

Re: [PERFORM] hyperthreaded cpu still an issue in 8.4?

, perhaps it is a problem in the name server, bind. But wherever it is, it bugs me. -- .~. Jean-David Beyer Registered Linux User 85642. /V\ PGP-Key: 9A2FC99A Registered Machine 241939. /( )\ Shrewsbury, New Jerseyhttp://counter.li.org ^^-^^ 13:55:01 up 6 days, 3:52, 3

Re: [PERFORM] random slow query

, software interrupt. It also shows disk read, write, and idle time. Lots of other stuff too. -- .~. Jean-David Beyer Registered Linux User 85642. /V\ PGP-Key: 9A2FC99A Registered Machine 241939. /( )\ Shrewsbury, New Jerseyhttp://counter.li.org ^^-^^ 14:55:01 up 12

Re: [PERFORM] Utilizing multiple cores in a function call.

-- .~. Jean-David Beyer Registered Linux User 85642. /V\ PGP-Key: 9A2FC99A Registered Machine 241939. /( )\ Shrewsbury, New Jerseyhttp://counter.li.org ^^-^^ 10:40:01 up 10 days, 21:29, 3 users, load average: 4.19, 4.22, 4.19 -- Sent via pgsql-performance

Re: [PERFORM] understanding postgres issues/bottlenecks

been up almost a month. It run RHEL5. I would think Fedora's kernel would probably be OK, but the other bleeding edge stuff I would not risk a serious server on. - -- ~ .~. Jean-David Beyer Registered Linux User 85642. ~ /V\ PGP-Key: 9A2FC99A Registered Machine 241939

Re: [PERFORM] Need help with 8.4 Performance Testing

Baltimore, MD | - -- ~ .~. Jean-David Beyer Registered Linux User 85642. ~ /V\ PGP-Key: 9A2FC99A Registered Machine 241939. ~ /( )\ Shrewsbury, New Jerseyhttp://counter.li.org ~ ^^-^^ 07:55:02 up 5 days, 18:13, 4 users, load average: 4.18, 4.17, 4.11 -BEGIN PGP SIGNATURE

Re: [PERFORM] file system and raid performance

MHz processors and 512 Megabytes RAM running RHL 7.3, and the new machine for postgres has two 3.06 GBYte hyperthreaded Xeon processors and 8 GBytes RAM running RHEL 5, so a comparison would be kind of meaningless. -- .~. Jean-David Beyer Registered Linux User 85642. /V\ PGP-Key

Re: [PERFORM] With 4 disks should I go for RAID 5 or RAID 10

-David Beyer Registered Linux User 85642. /V\ PGP-Key: 9A2FC99A Registered Machine 241939. /( )\ Shrewsbury, New Jerseyhttp://counter.li.org ^^-^^ 11:00:01 up 10 days, 11:30, 2 users, load average: 4.20, 4.20, 4.25 ---(end of broadcast

Re: [PERFORM] Utilizing multiple cores for one query

not happen by simply watching at the CPU utilization graphs when executing a query. Nevertheless, those people may wonder why (some of) those items that already run in parallel not actually run in parallel using multiple cores? - -- .~. Jean-David Beyer Registered Linux User 85642. /V

Re: [PERFORM] Query only slow on first run

the overall performance issue vs. the performance of this special query. -- .~. Jean-David Beyer Registered Linux User 85642. /V\ PGP-Key: 9A2FC99A Registered Machine 241939. /( )\ Shrewsbury, New Jerseyhttp://counter.li.org ^^-^^ 16:55:01 up 2 days, 22:43, 0 users

Re: [PERFORM] autovacuum: recommended?

to use .rpms from other sources, I can get in a lot of trouble with incompatible libraries. And I cannot upgrade the libraries without damaging other programs. -- .~. Jean-David Beyer Registered Linux User 85642. /V\ PGP-Key: 9A2FC99A Registered Machine 241939

Re: [PERFORM] autovacuum: recommended?

Bill Moran wrote: In response to Jean-David Beyer [EMAIL PROTECTED]: Decibel! wrote: On Nov 18, 2007, at 1:26 PM, gabor wrote: hubert depesz lubaczewski wrote: On Fri, Nov 16, 2007 at 10:40:43AM +0100, Gábor Farkas wrote: we are moving one database from postgresql-7.4 to postgresql-8.2.4

Re: [PERFORM] Curious about dead rows.

TX packets:30097919 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0 RX bytes:931924602 (888.7 MiB) TX bytes:931924602 (888.7 MiB) -- .~. Jean-David Beyer Registered Linux User 85642. /V\ PGP-Key: 9A2FC99A Registered Machine

Re: [PERFORM] Curious about dead rows.

Merlin Moncure wrote: On Nov 13, 2007 9:26 PM, Jean-David Beyer [EMAIL PROTECTED] wrote: Merlin Moncure wrote: what does pg_stat_all_tables say (assuming row level stats are on)? It says stuff like this: relname | seq_scan | seq_tup_read | idx_scan | idx_tup_fetch | n_tup_ins | n_tup_upd

Re: [PERFORM] Curious about dead rows.

Andrew Sullivan wrote: On Wed, Nov 14, 2007 at 07:12:45AM -0500, Jean-David Beyer wrote: I know there have been rollbacks but I do a REINDEX, CLUSTER, and VACUUM ANALYZE before starting the inserts in question. Do I need to do a VACUUM FULL ANALYZE instead? I had another idea. As Alvaro

Re: [PERFORM] Curious about dead rows.

Andrew Sullivan wrote: On Wed, Nov 14, 2007 at 07:12:45AM -0500, Jean-David Beyer wrote: I know there have been rollbacks but I do a REINDEX, CLUSTER, and VACUUM ANALYZE before starting the inserts in question. Do I need to do a VACUUM FULL ANALYZE instead? I had another idea. As Alvaro

Re: [PERFORM] Curious about dead rows.

Alvaro Herrera wrote: Jean-David Beyer wrote: Mario Weilguni wrote: Did you rollback some transactions? It will generate dead rows too - at least I think so. No, and the statistics confirm this. To recap: - your app only does inserts True. - there has been no rollback lately True

Re: [PERFORM] Curious about dead rows.

Mario Weilguni wrote: Jean-David Beyer schrieb: I am doing lots of INSERTs on a table that starts out empty (I did a TRUNCATE on it). I am not, AFAIK, doing DELETEs or UPDATEs. Autovacuum is on. I moved logging up to debug2 level to see what was going on, and I get things like this: vl_as

Re: [PERFORM] Curious about dead rows.

where someone like me would find it, so we would not have to go through this again for someone else. -- .~. Jean-David Beyer Registered Linux User 85642. /V\ PGP-Key: 9A2FC99A Registered Machine 241939. /( )\ Shrewsbury, New Jerseyhttp://counter.li.org ^^-^^ 22:05:01 up

Re: [PERFORM] Curious about dead rows.

-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 Andrew Sullivan wrote: Please don't drop the list, as someone else may see something. On Tue, Nov 13, 2007 at 10:06:13AM -0500, Jean-David Beyer wrote: OK. I turned logging from none to mod and got a gawdawful lot of stuff. Yes. Then I ran

Re: [PERFORM] Curious about dead rows.

Andrew Sullivan wrote: I'm not a private support organisation; please send your replies to the list, not me. Sorry. Most of the lists I send to have ReplyTo set, but a few do not. And then I forget. On Tue, Nov 13, 2007 at 04:57:23PM -0500, Jean-David Beyer wrote: What is it controlled

Re: [PERFORM] Curious about dead rows.

Merlin Moncure wrote: On Nov 10, 2007 1:38 PM, Jean-David Beyer [EMAIL PROTECTED] wrote: Tom Lane wrote: Jean-David Beyer [EMAIL PROTECTED] writes: I am doing lots of INSERTs on a table that starts out empty (I did a TRUNCATE on it). I am not, AFAIK, doing DELETEs or UPDATEs. Autovacuum

[PERFORM] Curious about dead rows.

doing UPDATEs. postgresql-8.1.9-1.el5 -- .~. Jean-David Beyer Registered Linux User 85642. /V\ PGP-Key: 9A2FC99A Registered Machine 241939. /( )\ Shrewsbury, New Jerseyhttp://counter.li.org ^^-^^ 11:15:01 up 18 days, 4:33, 4 users, load average: 6.18, 5.76, 5.26

Re: [PERFORM] Curious about dead rows.

Tom Lane wrote: Jean-David Beyer [EMAIL PROTECTED] writes: I am doing lots of INSERTs on a table that starts out empty (I did a TRUNCATE on it). I am not, AFAIK, doing DELETEs or UPDATEs. Autovacuum is on. I moved logging up to debug2 level to see what was going on, and I get things like

Re: [PERFORM] Curious about dead rows.

Joshua D. Drake wrote: On Sat, 10 Nov 2007 13:38:23 -0500 Jean-David Beyer [EMAIL PROTECTED] wrote: Tom Lane wrote: Jean-David Beyer [EMAIL PROTECTED] writes: I am doing lots of INSERTs on a table that starts out empty (I did a TRUNCATE on it). I am not, AFAIK, doing DELETEs or UPDATEs

Re: [PERFORM] Curious about dead rows.

-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 Scott Marlowe wrote: On Nov 10, 2007 1:57 PM, Jean-David Beyer [EMAIL PROTECTED] wrote: Joshua D. Drake wrote: Truncate will not create dead rows. However ROLLBACK will. Are you getting any duplicate key errors or anything like that when you

Re: [PERFORM] Bunching transactions

Heikki Linnakangas wrote: Jean-David Beyer wrote: My IO system has two Ultra/320 LVD SCSI controllers and 6 10,000rpm SCSI hard drives. The dual SCSI controller is on its own PCI-X bus (the machine has 5 independent PCI-X busses). Two hard drives are on one SCSI controller and the other

Re: [PERFORM] Bunching transactions

. -- .~. Jean-David Beyer Registered Linux User 85642. /V\ PGP-Key: 9A2FC99A Registered Machine 241939. /( )\ Shrewsbury, New Jerseyhttp://counter.li.org ^^-^^ 10:05:01 up 3 days, 2:23, 1 user, load average: 4.10, 4.24, 4.18 ---(end of broadcast

[PERFORM] Bunching transactions

whatever went wrong and start over anyway. But at some point, disk IO would have to be done. Is this just a function of how big /pgsql/data/postgresql.conf's shared_buffers is set to? Or does it have to do with wal_buffers and checkpoint_segments? -- .~. Jean-David Beyer Registered

Re: [PERFORM] Bunching transactions

Chris Browne wrote: [EMAIL PROTECTED] (Jean-David Beyer) writes: But what is the limitation on such a thing? In this case, I am just populating the database and there are no other users at such a time. I am willing to lose the whole insert of a file if something goes wrong -- I would fix

Re: [PERFORM] 12 hour table vacuums

is the biggest memory user. I set shared_buffers high to try to get some entire (small) tables in RAM and to be sure there is room for indices. -- .~. Jean-David Beyer Registered Linux User 85642. /V\ PGP-Key: 9A2FC99A Registered Machine 241939. /( )\ Shrewsbury, New Jersey

Re: [PERFORM] Low CPU Usage

/ % by the OS scheduler. When you query your CPU, it will say u are only using 5% or so... -- .~. Jean-David Beyer Registered Linux User 85642. /V\ PGP-Key: 9A2FC99A Registered Machine 241939. /( )\ Shrewsbury, New Jerseyhttp://counter.li.org ^^-^^ 08:15:01 up 6 days

Re: [PERFORM] Index files

for the table. -- .~. Jean-David Beyer Registered Linux User 85642. /V\ PGP-Key: 9A2FC99A Registered Machine 241939. /( )\ Shrewsbury, New Jerseyhttp://counter.li.org ^^-^^ 09:10:01 up 1:37, 4 users, load average: 5.77, 5.12, 4.58 ---(end

Re: [PERFORM] random_page_costs - are defaults of 4.0 realistic for SCSI RAID 1

, but that is pretty much of a record. -- .~. Jean-David Beyer Registered Linux User 85642. /V\ PGP-Key: 9A2FC99A Registered Machine 241939. /( )\ Shrewsbury, New Jerseyhttp://counter.li.org ^^-^^ 06:35:01 up 33 days, 9:57, 0 users, load average: 4.06, 4.07, 4.02

Re: [PERFORM] random_page_costs - are defaults of 4.0 realistic for SCSI RAID 1

-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 Gregory Stark wrote: Jean-David Beyer [EMAIL PROTECTED] writes: Gregory Stark wrote (in part): The extra spindles speed up sequential i/o too so the ratio between sequential and random with prefetch would still be about 4.0. But the ratio

Re: [PERFORM] DRBD and Postgres: how to improve the perfomance?

a couple hundred yards up the hill (but at least I needn't worry about Invest in sponges. Lots of them. :) -- .~. Jean-David Beyer Registered Linux User 85642. /V\ PGP-Key: 9A2FC99A Registered Machine 241939. /( )\ Shrewsbury, New Jerseyhttp://counter.li.org ^^-^^ 22

Re: [PERFORM] Hardware spec

limited. That way you could increase what needs to be increased, and not waste money where the bottleneck is not. - -- .~. Jean-David Beyer Registered Linux User 85642. /V\ PGP-Key: 9A2FC99A Registered Machine 241939. /( )\ Shrewsbury, New Jerseyhttp://counter.li.org

Re: [PERFORM] Hardware spec]

-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 Willo van der Merwe wrote: Jean-David Beyer wrote: -BEGIN PGP SIGNED MESSAGE- Hash: SHA1 Willo van der Merwe wrote: Richard Huxton wrote: Willo van der Merwe wrote: Hi guys, I'm have the rare opportunity to spec the hardware

[PERFORM] About autovacuum

I have this turned on, and if I look at the log, it runs once a minute, which is fine. But what does it do? I.e, it runs VACUUM, but does it also do an analyze? -- .~. Jean-David Beyer Registered Linux User 85642. /V\ PGP-Key: 9A2FC99A Registered Machine 241939

Re: [PERFORM] update query taking too long

it because it was cheap at the time and I was afraid it would become unavailable later. It is usually between 2/3 and 3/4 used by the cache. When I run IBM DB2 on it, the choke point is the IO time spent writing the logfiles. -- .~. Jean-David Beyer Registered Linux User 85642. /V\ PGP

Re: [PERFORM] Performance query about large tables, lots of concurrent access

for the database in question. (The other two are about 80 GBytes each, which is enough to run Linux and my other stuff on.) -- .~. Jean-David Beyer Registered Linux User 85642. /V\ PGP-Key: 9A2FC99A Registered Machine 241939. /( )\ Shrewsbury, New Jerseyhttp