English

In some discussions in mail and in some community forums linking to the articles about deduplication and hashing there was a slight misunderstanding. I should explain some things.

There was some discussion about possible attack vectors for checksum-only deduplication. However i don't think the proposed vectors are really feasible. The first attack tries to create data corruption by foiling deduplication into using a thoughtfully created block, with the same checksum but different data. Another, less discussed attack vector, is gaining knowledge of a block by using a thoughtfully created block to foil dedup to show you a different block than the one you have actually written, as the checksum-only variant didn't stored your block, but just created a pointer to data written beforehand.

Humans have a design flaw, they don't have a sense for risks. When you look at the risks from a more scientific perspective, the probability of dying in a terror attack is vastly lower than the probability of dying because you've committed suicide. With a realistic view to the risks, you should look in the mirror each day and observe yourself, not to other peoples in the aircraft, the subway or somewhere else. However the fear-mongers were able to implant us other feelings and so we strip-search people looking differently from us, we even start to strip-search everybody by technology like backscatter scanners.

Why do i talk about this? Well ... there is an technology in ZFS, that allows you to work with probabilities to speed up things. It's the deduplication part. You can use it in a way, that doesn't verify bit-for-bit if a block is really identical to another before just storing a pointer to the already stored block.

There is an interesting read at the Seek Alpha website. They published the Oracle+Sun Strategy Update Analysts call as a transcript. Gives some interesting information about the plans to make Sun's business profitable in year 1.

The usual suspect announced the second beta of the upcoming Virtual Box 3.1.4. You can download the beta here. As you may recognize while looking at the changelogs of Beta1 and Beta2, the 3.1.4 release is dominated by fixes instead of new features.

Jonathan Schwarz announced his last day at Sun with this tweet roughly an hour ago:

Today's my last day at Sun. I'll miss it. Seems only fitting to end on a #haiku. Financial crisis/Stalled too many customers/CEO no more

Of course it's a little bit tedious to zip cables from your switch to test IPMP or to deconfigure an interface to force traffic on different interfaces when you want to do some maintainance work in your network. There is an command to on- and offline physical connections in an IPMP group. It's called if_mpadm.

Unbeknownst to many people (including me), IKEA sells a modular rack system. A colleague hinted me to correct product at the IKEA website.. The product name is LackRack. For further technical indepth information you should visit this website of a IKEA rack customer. Albeit i don't think this rack will have a high "Significant Other Acceptance Factor", it's surely better than the one of a full size Sun rack in the living room.

When you work with the interesting features of Solaris, you forget about the small features in commands you use day by day. In my my IPMP tutorial i used an SMF script to make some host routes persistent ... at foremost to show you that SMF scripts are really easy. But, well ... this script isn't nescessary because of the -p option of the route add command.

Looks like, Tukwila was released. Intel PR writes:

"Tukwila," the code name for the newest Itanium processor, has begun revenue shipments. The most advanced Itanium processor yet, "Tukwila" more than doubles the performance of its predecessor and adds a range of new scalability, reliability, and virtualization features

Just three years late

The Power7 launch may be imminent, too. IBM invited to a series of events in Germany on this webpage. There is an event called "IBM POWER Vorstellung" and the headline is "Experience the next generation at the POWER event ...". Don't think, they will just announce a speed bump. And i was told, an earlier version of the page contained the 7. I'm really interested, if they will announce some prices (the Power7 is a large beast as far as i know, will be expensive), benchmarks (still thinking that the single thread will be slower, than at Power6 ... well ... Power7 is IBMs implementation of the basic CMT idea: more cores, but simpler cores ... no offence in this statement ) and if they will announce upgrade paths for older systems.

Will be nice to make some competitive comparision based hard numbers, not just on informed assumptions.

One of the interesting features of Solaris x86 missing in the SPARC variant is the support for fast reboot. Fast reboot reduces the boot times, as it skips firmware and boot loader. The old kernel loads the new kernel and passed the control to the new one. With PSARC 2010/030 the SPARC variant of Solaris will get fast reboot, too.

While helping a colleague to answer some questions of a customer, i've was somewhat puzzled about the fact that there aren't many new SAP SD benchmark result IBM Power systems. There is just one result. It's a small p550 with 4 Power6 CPUs. But i forgot about that, because i had many other things to do.

Jan Brosowski wrote about an interesting speculation in his blog article "Es liegt vor allem an Solaris", which could explain this development.

His blog article is in german, thus i will summarize the interesting part here in english: There is a new rule in the SAP-SD benchmarking. When you have to separate the application server and the database server into two separate virtual machines (like using two LPARs) it isn't a 2-tier benchmark, it's a 3-tier benchmark. You could speculate, if IBM needs this separation to get all the horsepower of the large systems onto the street. Perhaps to have better control on used resources or just to improve the scalability of the system (perhaps you remember the TPC-H benchmark that used 32 IBM p570 nodes in a 32 system images configuration instead of a 8 system images configuration as you are able to connect 4 p570 nodes into a single system as an example of a strange benchmarking configuration that didn't used the scaling capabilities of a system). You could speculate if there's a scaling challenge in the IBM systems (in the HW or in the OS) when used with a single OS image. Such an challenge can be solved by using partitions. But with partitions activated, they couldn't submit a 2-tier SAP SD result.

Well ... from my point of view i get more and more cautious when IBM tries to extrapolate the big systems performance in benchmarks by using the results of smaller systems even when they introduce a scaling correction factor. I would really like to see a SAP SD 2-tier result of a p595 or at least a full-blown p570.

I really like to give presentations. Thus i'm looking at new devices from the perspective "Do they make my life easier in regard of giving presentations?". And somehow i believe the Apple iPad could be the ultimate presentation device on-the-road. More than enough storage for my presentations, there is an Keynote version on the device to make last-minute-changes with a display large enough to make changes, with a Dock2VGA cable you have 1024*756 (pretty much the standard for meeting room beamers) and it's lightweight. Would be nice to carry around just such a device instead of a full notebook. I want one

Brendan Gregg made some test runs to measure the impact of the new iSCSI implementation in the Sun Storage S7000 series and wrote about it in his article "iSCSI before and after". Just as an explanation: Early versions of the S7000 firmware used the usermode iSCSI target implementation. While usable it was somewhat slow compared. 2009.Q4 changed that by using the COMSTAR iSCSI target.

Brendan was able to measure the impact of this change. The old implementation yielded 311 MByte/s and 37056 512-byte IOPS. The new implementation yielded 2.70 GByte/s and 318.099 512-byte IOPS. Albeit some of the performance increases are due to the move from Quadcore to Hexacore Opterons, i think Brendan is right with his statement at the beginning of the article:

It would of course be better to split the results showing the COMSTAR and hardware update effects separately - but I only have the time to blog this right now (and I wouldn't be blogging anything without Joel's help to collect results.) I would guess that the hardware update is responsible for up to a 2x improvement, as it was for NFS. The rest is COMSTAR.

Just in case you hadn't the opportunity to view the webcast about the future directions of Sun inside of Oracle yesterday, you will find the recorded webcasts and the pdfs of the presentations on Oracles website now.