Well, a 10 hour plane journey has been undertaken since the last day of OpenWorld actually happening and me typing this up, so it’s all bit old news really. After an evening spent with Roger Daltrey, as opposed to Aerosmith, I was not entirely appreciative of several hours more of technical presentations.
Which was a shame as on Thursday I went to a couple of quite technical presentations and a cracking round table discussion.
ACFS: The Awaited Missing Feature – Matthias Pölzinger
This was quite a deep delve into the ASM Cluster File System. Quite technical for OpenWorld, and Matthias certainly knew his stuff.
Oracle and cluster file systems
Bit of a history of Oracle and cluster file systems
First clustering attempts in parallel server 6.2
RMS or raw
CFS certified in 9i
ASM released with 10.1, but only limited support for certain file types.
the missing component
ACFS is posix compliant can store oracle homes, application data
ACFS support NFS/CIFS built on all standard ASM storage management features
online file system expansion
snapshotting built in.
structure of ASM CFS
diagram – might have been better to fly pieces in that slapping it all at once.
ADVM = ASM Dynamic Volume Manager
now showing a nice diagram having split up some disks into an APPDATA diskgroup, some disks into a GRIDDATA (OCR/Voting) Diskgroup and finally some disks into the DATABASE datafiles diskgroup
you can create ext3 filesystem upon an ADVM volume.
3 new kernel modules
responsible for all acfs file/directory operations
presents block devices for advm volumes
There are quite a few new ASM background processes.
fields of application
share external data, bfiles, external tables, external files.
multi-node fault tolerant data loading
shared database oracle homes
server OS has valid OEL support contract
one cluster node is correctly licensed according to SE or EE
no need for 3rd party CFS or NAS. Will be a uniform platform independent solution, will eventually be rolled out to other platforms, currently only linux.
I’m suspecting it might be endian-neutral
showing an example of going from disks to provisioned acfs. Using xml file to create the diskgroup. Using asmcmd and the mkdg command.
bonie++ benchmakr comparing both OCFS2 and ACFS. using NettAPP filers for the storage and a 2node cluster. graphs showing comparison 74MB to 48 for reading,while 51 to 36 for input. ACFS is considerably faster according to this benchmark, that is 50% speedup. This sounds like quite a potential speedup for anyone using OCFS2
ACFS does not support directio.
There was even a good set of questions at the end, though there does seem to be a lot of confusion over what you can and what you cannot store within ACFS.
Next up for me was:
Oracle Net Services: Best Practice – Kant Patel
Quite a lot of really useful information in this one on who to get the maximum performance and availability out of your listener, and how to maximise the scalability of it. There was a lot of information, just wish it had come earlier in the week and I might have made a bitter stab at capturing more of it. I’ll certainly be going over the slides (on demand registration required) at some point.
Again there was also a mass of questions, which always seems to add a lot of value to a presentation, however, I really think it’s quite rude for about 3/4’s of the audience to stream out chatting away. At least go quietly!
Real-World Database Performance Roundtable
I missed this last year due to flying home in the early afternoon, but I was leaving a bit later this year, and I think this session was on a bit earlier than last year. The format of this is superb, basically little cards are handed round and the audience is invited to write their performance questions, which then a top-notch panel from the Real World Performance Group then answer.
There was some good discussions on Optimizer statistic collection and on the various merits of Sparc T2 series chips compared to x86. The Oracle people were saying if you want to run multiple concurrent processes doing small amounts of OLTP work then the T2 chips were fine, though each individual thread goes at a much slower clock rate than, for example your Nehalem chips. Andrew Holdsworth though, very much put in the caveat that it is a rare system that exclusively does just OLTP type lookups, and most if not all systems have a mixed workload.
Very much came out that there are no magic bullets and it is very, very often that poorly performing SQL or badly designed systems are at the root cause of 99%+ of all performance issues.
This style of event where the audience ask questions on cards is an excellent one, and this event really worked quite well.
Had lunch with Simon Haslam, and we both noticed that OpenWorld was starting to look a little bit deserted by lunchtime on Thursday. After that it was time for me to clear off to the airport, while trying to avoid the swarming hoardes of cops and security service personnel in town for Obama’s visit. Didn’t see him myself, sadly. I’m sure it’s only a matter of time before Larry has him up on stage during the Larry Keynote, 2010 anyone?