Saturday, September 24, 2011

My LIO silly little benchmark

I have been working on a benchmark for LIO.  I know there are TPC and TPH transactions numbers that are published, on CPU speeds, but how much does that directly releate to LIO's, the heart of an Oracle database ?

  To help benchmark, I wrote a little pl/sql package.  This packages takes the Zip Code database, and randomly picks  some rows with a cursor (about 1 % of the table).  This package is then called by swing bench, and I put a "think time" in it for each execution of the package.

Ideally, I try to execute it up to what the Server can handle.. This was especially usefull with the benchmarking I did in a previous post on hyperthreading.

I was interested in what anyone else does ?  I try to do a LIO lookup, and compare numbers between servers.  By doing this I have a pretty good idea how many LIO's an AMD server can handle per second, an Intel server can do, and different architectures (2 socket, 4 socket, and 8 socket).. I even benchmark virutalization to see how much of an overhead is caused from the Software.

This may not be the best way (it excludes what happens with updates (redo logs etc), and how much physical I/O's affect the workload.

Any ideas would be appreciated.  I would love to come up with a nice reproducable benchark, and then maybe create a dbcapute of it, and do a dbreplay on different architectures ? Would that be more accurate.

I know many of you will say the line "well it depends on the workload", maybe the benchmarking that comes with swingbench is good enough ??

I'm just tired of reading server bencharks, and finding that for an oracle database, those benchmarks aren't very meaningful.

I would also love to do some benchmarking with Solaris X86, and RHEL/OEL on an 8 socket box.

I would also love to learn what anyone else has learned ?  I am especially interested how 8 socket intel servers compare with 2 socket. I'm seeing some pretty increadable numbers from 2 socket servers (almost 2x the speed of 8 socket).  I'm wondering if anyone else is seeing some measureable differences.

I'm starting to move to "go wide"  camp rather than go high camp for increasing server power.  The blade servers are being more, and more powerful, and you can have more memory local to the CPU. Increasing CPU sockets just increases hops to get those LIO's done, costing time, waits, latches. etc. etc.

So here is a piece of my LIO benchmark...


CREATE TABLE "KILLER" ("CC_ID" NUMBER(20, 0) NOT NULL ENABLE)  ;

/*  import 55,000 rows of distinct data */
CREATE PROCEDURE          kill_lio IS
   my_count number := 1;
   my_executions number;
   my_buffer_gets number
   my_cpu_time number;
   my_elapsed_time number;

error_code number;

BEGIN
for i in 1..10000 LOOP


select count(distinct cc_id) into my_count from kill_lio.killer;

end loop;

select executions,buffer_gets,cpu_time,elapsed_time into my_executions,my_buffer_gets,my_cpu_time,my_elapsed_time 
from sys.v_$sqlstats where sql_id='2j5tvp5rdzmym';
 
 dbms_output.put_line('exectutions:                          ' || to_char(my_executions,'999,999,999'));"
dbms_output.put_line('buffer gets:                          ' || to_char(my_buffer_gets,'999,999,999'));"
dbms_output.put_line('cpu time:                             ' || to_char(my_cpu_time,'999,999,999'));"
dbms_output.put_line('elapsed time:                         ' || to_char(my_elapsed_time,'999,999,999'));"
dbms_output.put_line('elapsed time per execution(ms)   :      ' ||to_char( my_elapsed_time/my_executions/1000,'999,999.9'));"
dbms_output.put_line('buffer_gets/second:                   ' ||to_char( my_buffer_gets/(my_elapsed_time/1000000),'999,999,999'));"

END;  -- exception handlers


and here is the output I use to compare.  I look at the average elapsed time, and buffer_gets/second to benchark systems.

executions:                                 10,000
buffer gets:                             1,190,000
cpu time:                              190,983,974
elapsed time:                          191,374,061
elapsed time per execution(ms)    :           19.1
buffer_gets/second:                          6,218


Here is the AWR report from the execution

Wednesday, September 21, 2011

Oracle Database Appliance

I have spent the day on an oracle call, and reading all the subsequent tweets that follow.  I think the best way to describe the appliance is that it is NOT a mini-exadata, but it is a simple rac appliance.

My impression is that it is a nice product for the small to mid market, but those us working with the bigger toys I don't see the gain.

I know, I've spent more days than I care to remember schooling the SA's on how to set up an interconnect, and ensure that all the IP's are correct.  I've worked with Storage administrators on how to present the disks, and make them available to ASM, and I've worked with networking on the ranges of IP's I need for scan, interconnect, etc. etc.  I'm sure you get the picture.

I also think that people like me that work in a big organization and have a team to handle these tasks, are probably going huh ? what is this? 

Personally, I don't see the big deal in this.. I see lots of dissadvantages.

  • These Appliances cannot be clustered. What they have in them is all they will ever have in them.
  • The 2 database nodes have 96g of memory, not a lot in today server sizes..
  • There is no storage software like the exadata. No HCC, no offloading, no infiniband
  • This is local disk in the appliance, meaning no cloning, storage virtualization, etc.
  • The interconnect is 1ge, not infiniband.
  • You CANNOT hook up fiber to this server, ever.
  • It runs OEL, NOT redhat linux.. the differences are getting greater over time.
  • This is a closed system with specific patch sets that need to be maintained to a short list of acceptable patches.
I know for a small, to midsize, the ideal of creating a new rac system in 2 hours is thing of beauty, but for bigger companies, there isn't a lot there.

Especially without the Exadata candy filling (infiniband, HCC, offloading, storage indexes).

I still think virtualiation is the direction, and this is a step in the opposite direction.  There may be a few takers, but I think companies will realize that virtualization is a better direction than a single closed appliance.

We will see.. just some thoughts.

Saturday, September 17, 2011

Delphix, Solaris and ZFS

I was inspired to write a new blog posting after seeing a great presentation on Delphix.  Delphix is an extremely interesting product to help with the managing of many copies of an oracle database.  This product goes hand-in-hand with a virtualization product like VMWARE. What VMWare is servers, Delphix is to storage.

First I want to babble on a bit.. Why ? Because this is my blog.

I have used Solaris for many years and I am a big fan of Sparc/Solaris, and everything that it became over the years.  I know in the last couple of years, it has kind of fallen down, and Linux x86 has been growing leaps and bounds.  The most impressive piece of Solaris however has been ZFS.  ZFS offers snapshotting, cloning, lots of fantastic options built into the OS.  All very easy for the DBA.

I was very excited when ACFS came out (anyone remember).  It was the coolest thing going.  It looked a lot like ZFS built on top of ASM.   It had the potential to become a fantastic tool.  I was really, really, really hoping that down the road ACFS, and ZFS would combine, and replace the cooked file system with an Oracle File System that Rocked.    Well in case you didn't know ACFS has morphed into the "Cloud File System" or Cloud FS.  This is a licensed product used for the sharing of directories in a "cloud" environment.  Also, if you didn't know, ACFS won't run on the Exadata.  2 nails in the Coffin of this fantastic vision that I had in my head.

I was devastated for a while.

Why the background ? Because Delphix picked up where this vision died.  They offer the ability to do snapshots, along with deduplication, and compression to boot.

Delphix was founded by Jedidiah Yueh, who founded Avamar (dedup software that was sold to EMC),  The company also has  Karthik Rau, ad VP of Products who worked on VMware.  Lots of very bright people that were already involved in the founding technology.

Delphix makes the creation of database copies, easy, and it save space to boot.  I will post the presentation that I saw once I can link to it.

Definitely something worth checking out, and to watch for in the infrastructure Arsenal.