The latest release of DBD::Oracle is now ready and can be found at: CPAN DBD::Oracle. It is a Perl module that works with the DBI module to provide access to Oracle databases. It is maintained by me, John Scoles as open source/free software, under the auspices of The Pythian Group. The release has been fully tested [...]

Fast arrays, wild women, crazy nights… and database access times to disk based files. Here are some results from various dev servers I have.

 2x 147GB SCSI U320 drives in hardware RAID-1
#-(root@sunfire)-(/home/user)-#
#-(0)> hdparm -t /dev/mapper/VolGroup00-LogVol00
Timing buffered disk reads:  172 MB in  3.02 seconds =  56.93 MB/sec
#-(0)> hdparm -T /dev/mapper/VolGroup00-LogVol00
Timing cached reads:   1450 MB in  2.00 seconds = 724.77 MB/sec

2x 10GB SCSI U160 disks in software RAID-1
#-(root@sgi)-(~)-#
#-(0)> hdparm -t /dev/md0
Timing buffered disk reads:   36 MB in  3.19 seconds =  11.28 MB/sec
#-(0)> hdparm -T /dev/md0
Timing cached reads:   306 MB in  2.00 seconds = …

While some colleagues have already arrived in Orlando to meet fellow MySQLers, my plane from FRA to MCO (via DTW) does not leave until 10:20am tomorrow. Currently I am staying at my parents' place in Heidelberg, from which I will be picked up by an airport shuttle service early tomorrow morning (5:40am, ugh!).

I am looking forward to meeting with the other members of my team as well as old and new colleagues from the different departments. There seems to be some kind of outdoor team building event taking place on Wednesday afternoon - we have been split up into mixed groups and were asked to bring comfortable clothes and a light sweater or jacket. I hope I am not too jetlagged by the end of the day...

This will be my fourth MySQL staff meeting - when I joined the company in 2002, I was lucky to attend the third staff meeting in St. Petersburg, Russia right during the first week when I started my new job. Back then, we …

… is coming soon. We were just about to release beta 5.0.12 out into the wild on friday, but it looks as if it wasn’t meant to be. I found some nasty issues in the latest fixes we did, so we had to correct those before we can set it free.

Again many bugs have been fixed since version 5.0.11 so stay tuned for the upcoming new release.

Listening to many recruiters and hiring managers talk about how difficult it is to find MySQL certified professionals, I've created a MySQL Certified Professionals group on LinkedIn. What is LinkedIn? LinkedIn is an online network of more than 17 million experienced professionals from around the world, representing 150 industries.

This MySQL group is only for certified professionals, technical recruiters, hiring managers or human resource managers to help locate MySQL Certified Professionals in your area. If you have any of the MySQL certifications, you can sign up on LinkedIn. You need to email me your MySQL ID and public password to verify your certification on the MySQL website. If you're a recruiter, hiring manager or human resources professional you can also join this …

Here for the MySQL All Company Meeting. Arrived okay… albeit late (got to stop in two cities I didn’t intend to). Had breakfast with Monty, Monty and Giuseppe and a few cups of coffee later… it sorta feels like morning.

My world tour includes mostly warm places (Orlando, Los Angeles, Australia, Singapore), but to cover the first leg, Munich, I needed warm clothes (cover is the operative word here).
Thus, when I saw a skilled craftsman creating customized hats and scarfs, I couldn't resist.
The weather in Orlando does not require such gear. This is a view form my hotel room.
. We are going to have MySQL company meeting in this beautiful place. For now, I am just nursing my jet lag and preparing to meet a few hundred colleagues.

mysql-5.0.51 causes huge blocking locks under high load.

It also causes relay-log corruptions. For instance, how can a syntax error make it into replication, the reason is mysql-5.0.51 is truncating the stream.

The only work around is to rebuild the relay log.

The BUG is listed here for replication problems. I suspected IO_CACHE corruption as the cause.



update: this is the cause of the huge blocks

InnoDB: Warning: a long semaphore wait:
--Thread 1173899616 has waited at btr0cur.c line 424 for 292.00 seconds the semaphore:
S-lock on RW-latch at 0x2df5159f58 created in file buf0buf.c line 497
a writer (thread id 1173899616) has reserved it in mode  exclusive
number of readers 0, waiters flag 1
Last time read locked in file btr0cur.c line 424
Last time write …

O_DIRECT under high load causes these issues

This is a symptom

Losing some ticks... checking if CPU frequency changed.
warning: many lost ticks.
Your time source seems to be instable or some driver is hogging interrupts
rip __do_softirq+0x4d/0xd0
ttyS1: 1 input overrun(s)
ttyS1: 1 input overrun(s)
ttyS1: 1 input overrun(s)
ttyS1: 1 input overrun(s)
ttyS1: 1 input overrun(s)



BUT THE REAL PROBLEM is it Locks up the partition that the ibdata file is on.


Systems where the server locked up.

2.6.9-34.ELsmp #1 SMP Fri Feb 24 16:56:28 EST 2006 x86_64 x86_64 x86_64 GNU/Linux

          total       used       free     shared    buffers     cached
Mem:      16412760   16389976      22784          0      82440     686368
-/+ buffers/cache:   15621168     791592
Swap: …

This will be one of those posts I’d like to publish primarily to be able to coma back later and check it out instead of reading docs again

So, we have a server with two (or more) network interfaces are we need to be able to use more than one interface in our VDS machines. How do we set it up?

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