Tuesday, September 30, 2008

SSH on Niagara T2

In build 99 of Open Solaris among other new features one is quite interesting - out of the box use of built-in HW acceleration of UltraSparc T2 in ssh. It semms like it can deliver over 2x speed-up for scp. And yes, it's going to be back ported to Solaris 10. You can read more here.

Virtual Consoles in Solaris

One of the missing features of Solaris used to be lack of Virtual Consoles - something we are accustomed so much in Linux. Solaris used to have virtual consoles once.. long long time ago, then they disappeared. Finally, they are coming back into Open Solaris and have been integrated into build 100.

Rock support in Open Solaris

Now, how do I get an access to beta HW with Rock on board?

Tuesday, September 23, 2008

Fast Reboot on x86

What if you have a x86 system with lots of memory and you want to reboot it? It will probably take minutes before your system starts booting. What if you could bypass BIOS and POST testing and go directly to bootloader? Such a nice feature has been just integrated into Open Solaris build 100. See PSARC 2008/382 for more details.

A new "-f" flag has been introduced to the "reboot" command
which allows a faster reboot that bypasses the BIOS and grub.

Thursday, September 18, 2008

MySQL Scalability

NetApp's PAM

NetApp introduced a new feature called PAM - Performance Acceleration Module.
"In the simplest terms, the Performance Acceleration Module is a second-layer cache: a cache used to hold blocks evicted from the WAFL® buffer cache. (WAFL is the NetApp® Write Anywhere File Layout, which defines how NetApp lays out data on disk. The WAFL buffer cache is a read cache maintained by WAFL in system memory.) In a system without PAM, any attempt to read data that is not in system memory results in a disk read. With PAM, the storage system first checks to see whether a requested read has been cached in one of its installed modules before issuing a disk read. Data ONTAP® maintains a set of cache tags in system memory and can determine whether or not a block resides in PAM without accessing the card. This reduces access latency because only one DMA operation is required on a cache hit."
It all sounds very good and is very, very similar to L2ARC feature in ZFS, except that it seems like NetApp only supports very expensive PCI/DRAM cards with relatively small capacity. With ZFS L2ARC not only you can get such functionality for free, but it is also more flexible and allows you to use any block device in a system as L2ARC - so you can provide hundreds of GBs of cache for a fraction of cost of NetApp's cards. And ZFS is open sourced :)

Intel SSD Drives

Intel announced some time ago new line of SSD drives. For a consumer market the X-25M looks very promising. You can read reviews here and here.

Thursday, September 04, 2008

VirtualBox 2.0

Sun has released new version of VirtualBox. Main new features are:

  • 64 bits guest support (64 bits host only)
  • New native Leopard user interface on MacOS X hosts
  • The GUI was converted from Qt3 to Qt4 with many visual improvements
  • New-version notifier
  • Guest property information interface
  • Host Interface Networking on Mac OS X hosts
  • Host Interface Networking on Solaris 10 hosts
  • Support for Nested Paging on modern AMD-V CPUs (major performance gain)
  • Framework for collecting performance and resource usage data (metrics)
  • Clipboard integration for OS/2 Guests
  • Support for VHD images
  • Created separate SDK component featuring a new Python programming interface on Linux and Solaris hosts

Wednesday, September 03, 2008

5 years of DTrace

It's been five years since DTrace has been integrated into Solaris.
It's one of the most important technologies in Operating Systems.

Read Bryan's blog entry on last few hours before integration.

I remember one of my first big dtrace wins - a multi-threaded application, developed in-house by our developers had some scalability problems on multi-cpu servers. They spent about a week looking for an issue without any progress. It was early just after dtrace was made public and I decided to give it a try. At first no real progress... while I was driving home the issue was still in a back of my mind. Suddenly I was 100% sure how to solve the issue with dtrace. First time in a morning I sat down with developers and we have fixed the problem in 5 minutes. We were working on a production code in a production environment. The era of DTrace has began...