Thanks Kevin. All but one (DEV) of our Oracle software installs were not linked with rat_on. It was done before I started here and I couldn't say why. So we need to relink with rat_on to capture the load on our production DB. Obvious downtime requirements, etc. Don. On Thu, Dec 5, 2013 at 5:51 PM, Kevin Jernigan <kevin.jernigan@xxxxxxxxxx>wrote: > [shameless plug for a product I manage at Oracle] Even though your > workload as described might not be a fit, you should still think about the > benefits of HCC on ZFSSA, which is fully supported with 11.2.0.3. If you > have licensed Partitioning, then you can partition your larger tables by > time, and use HCC on the older (and presumably "colder") partitions to > greatly reduce the storage requirements for those partitions, typically > 6x-10x with the "query" levels of HCC, and 15x++ with the "archive" levels. > > But to answer your real question, i.e. how to determine how frequently > data is read and re-read, that's not an easy question to answer in > 11.2.0.3. We added Heat Map in 12c to make it easy to track query and > modification times at the table, segment, and block (mods only) levels, but > prior to 12c, there's nothing built-in that will give you the details you > really need to project performance. > > You're better off focusing on using RAT or something similar to record or > simulate your real-world workloads, and then replay those workloads in a > test system with your ZFSSA storage in place. On that note, you say that > you have to do some re-linking to use RAT - can you elaborate on what you > have to re-link? > > Thanks, > > -KJ > > -- > Kevin Jernigan > Senior Director Product Management > Advanced Compression, Hybrid Columnar > Compression (HCC), Database File System > (DBFS), SecureFiles, Database Smart Flash > Cache, Total Recall, Database Resource > Manager (DBRM), Direct NFS Client (dNFS), > Continuous Query Notification (CQN), > Index Organized Tables (IOT), Information > Lifecycle Management (ILM) > (650) 607-0392 (o) > (415) 710-8828 (m) > > > On 12/5/13, 1:58 PM, Don Seiler wrote: > >> Good afternoon. Oracle 11.2.0.3. Currently on ASM but looking to migrate >> to the Oracle ZFSSA. The big selling point of the ZFSSA was the ARC and >> L2ARC caches backed by DRAM and flash. However we want to know if our >> application needs will be met here. We suspect that a fair amount of our >> I/O is for unique lookups that aren't repeated that often, and so likely >> would not be in the ZFSSA cache on subsequent executions. >> >> However I'd like to be able to determine for sure. I'm wondering if any >> list members have any suggestions on how to determine how frequently data >> is read and re-read so we can make realistic expectations on what the >> performance will be like for our application usage. >> >> We're looking at using RAT to capture a typical workload and then play it >> back on a "sandbox standby" that we have running on the ZFSSA now, but we >> have to wait for a downtime window to do some re-linking. Wondering if >> there are any alternatives that we can also look at. >> >> -- >> Don Seiler >> http://www.seiler.us >> > > -- Don Seiler http://www.seiler.us