By realneel on Jan 18, 2008
- Numerical Data (Throughput, Response time, etc)
- Textual Data (OS Patch level, syslog messages, etc.)
A major portion of my job (@ PAE) is spent trying to optimize Solaris for real customer workloads. We tend to focus on databases, but work with other applications too. We have tons (both weight wise and dollar wise ) of equipment in our labs, where we try to replicate a real enterprise data center. Of course, the term "real customer workload" is a loaded term. Since most big customers are rarely willing to share their workloads, we have to simulate them or write something close it in house. Trying to rewrite every customer's workload is not a scalable approach. Hence we have developed a workload called OLTP/Net that can be retrofitted to fit most customer workloads. Using several tuning knobs we can control the amount of reads, writes, network packet per transaction, connects, disconnects, etc.. Think of it like a super workload! We have used it quite effectively to simulate several customer workloads.
There is a big difference in trying to get the best numbers for a benchmark and in replicating a customer's setup. PAE has traditionally focused on getting the most out of the system. Our machines typically run at 100% utilization, run the latest and greatest Solaris builds, have lot of tunings applied to the system. We believe fully in Carry Millsap's statement
Each CPU cycle that passes by unused is a cycle that you will never have a chance to use again; it is wasted forever. Time marches irrevocably onward."
(Performance Management: Myths & Fact, Cary V. Millsap, Oracle Corp, June 28, 1999)
However, many customers run their machines at less than 100% utilization to leave enough headroom for growth. When machines are not running at 100% utilization, things like idle loop performance matter a lot. If you have followed Solaris releases closely, there were several enhancements to the idle loop performance that increase the efficiency of lightly loaded systems by quite a bit. Similarly we have seen quite a few UFS + Database performance enhancements over the past few releases of Solaris.
So while benchmark numbers do matter, real performance also matters, and we are working on it!
Richard Elling pointed it out that you could also use slice 2 (the loopback/backup/overlap slice) also. So that's 8. He also mentions that some SCSI devices support 16 slices, and so you could install quite a lot more OS installations! Maybe we should have a completion of how many OS's you have installed on a single disk My personal best is 6.
The goal is to have 6 bootable OS on a single disk. Why should one do it? Because better sharing, more reliability, easier comparisons between OS versions, quicker recovery, ...BTW, I have only tried this on sparc.
Although I am sure that people have been doing this for ages, I first heard it from Charles Suresh, who encouraged me to go ahead and give it a try.
0 root wm 2178 - 5655 4.79GB (3478/0/0) 10047942
1 swap wu 0 - 2177 3.00GB (2178/0/0) 6292242
2 backup wm 0 - 24619 33.92GB (24620/0/0) 71127180
3 root wm 5656 - 9285 5.00GB (3630/0/0) 10487070
4 root wm 9286 - 12915 5.00GB (3630/0/0) 10487070
5 root wm 12916 - 16545 5.00GB (3630/0/0) 10487070
6 root wm 16546 - 20175 5.00GB (3630/0/0) 10487070
7 root wm 20176 - 24619 6.12GB (4444/0/0) 12838716
filesys c1t1d0s0 existing /
filesys c1t1d0s1 existing swap
filesys c1t1d0s3 existing /s3 preserve
filesys c1t1d0s4 existing /s4 preserve
filesys c1t1d0s5 existing /s5 preserve
filesys c1t1d0s6 existing /s6 preserve
filesys c1t1d0s7 existing /s7 preserve
|[neel@slc-olympics] config > cat
[neel@slc-olympics] config >
I am Neelakanth Nadgir and I am a part of PA2E (Performance Architecture, and Availability Organization) group. I work out of Menlo Park, CA. My professional interests include scalability, networking, filesystems, distributed systems etc.
Before joining PA2E, I worked at Sun's Market Development Engineering, where I spent 4 years working on Performance tuning, Porting, Sizing, and ISV account management.
am was also involved with several open source projects. I am an active member of the JXTA community and jointly started two projects viz
Ezel Project and
JNGI Project. I have
also served as web-master to the
for 2 years. I also contributed to the
Mozilla project in the past by providing sparc binaries and misc performance fixes.
Before working at Sun, I graduated with a masters in Computer Sc from Texas Tech University at Lubbock, TX (GO Raiders!). My thesis was on the Reliability of distributed systems, where I devised a faster algorithm for calculating minimal file spanning trees. I have a Bachelor's degree in Computer Sc from Karnatak University, India.
My other interests include Cricket, and tropical aquarium fish ( African cichlids in particular) My favorite fish is known as Pseudotropheus demasoni. My wife got me hooked on to the aquarium hobby after we got married, and even before I knew, we had more than 60 fishes in 6 tanks :-)
I plan to use this blog to share the knowledge that I gained from working with lots of cool people here at Sun. Keep tuned for more insights!