In the last part of this installment I'll have a brief look at the network performance measured in the Oracle DBaaS environment, in particular the network interface that gets used as private interconnect in case of RAC configuration. The network performance could also be relevant when evaluating how to transfer data to the cloud database.
I've used the freely available "iperf" tool to measure the network bandwidth and got the following results:
Recently I repeated the I/O related tests on a 220.127.116.11 instance for curiosity and was surprised by the fact that I consistently got significantly better results as on 18.104.22.168 and 22.214.171.124.
Now you're probably aware that the version 12.2 so far is "cloud-only", so I can't tell / test whether the version 12.2 is generically providing that increased performance or whether Oracle has optimized (more...)
In this second part of this installment I'll focus on the performance figures related to I/O encountered when the corresponding tests were performed on the platform.
When running with minimum sized buffer cache, direct and asynchronous I/O enabled, the following average read-only IOPS figures were measured over a period of several days (this is the test described in part three of the "performance consistency" series) .
First, running on a 4 OCPU single instance configuration (more...)
I've encountered a bug at several clients that upgraded to Oracle 12c - 126.96.36.199 - that requires the combination of several new adaptive features introduced with Oracle 12c.It needs an execution plan that makes use of adaptive join methods, plus at runtime the activation of the new "statistics feedback for joins" feature that was also introduced with Oracle 12c. Note that in 11.2 there was already the "cardinality feedback" (more...)
After having looked at the performance consistency provided by the Oracle Database Cloud offering in the previous series, I'll focus here on the raw performance figures I've measured during my tests, starting with the CPU related performance findings.
One of the first surprises is related to the fact that Oracle uses a unit called "OCPU" to specify the CPU capacity provided, which is explained here:
So one "OCPU" is supposed to represent one core (more...)
This is just a prototype of a queue-based concurrent statistics implementation - using the same basic implementation I've used a a couple of years ago to create indexes concurrently.There are reasons why such an implementation might be useful - in 11.2.0.x the built-in Concurrent Stats feature might turn out to be not really that efficient by creating lots of jobs that potentially attempt to gather statistics for different sub-objects of the (more...)
This part of the series is supposed to cover the results of I/O related tests performed on the Amazon RDS Oracle cloud instance.
As mentioned in the previous part of this series I've only used the "General Purpose SSD" storage type since the "Provisioned IOPS" storage was simply to expensive to me and it wasn't possible to get a trial license for that storage type.
Now one key aspect of the "General Purpose SSD" storage (more...)
In the next parts of this series I'll have a look at the results of similar performance consistency tests performed on a comparable Amazon RDS Oracle cloud database instance.
Let's start with the configuration used, which was an Amazon RDS "db.m4.2xlarge" instance - the latest RDS generation available at time of testing. This is an 8 VCPUs resp. Hyper Threads / 4 cores configuration with 32GB of RAM.
This is the fifth part of this installment, and before coming to comparisons to other cloud providers, in this part I show the results of the read-only test that I've already described in part three of this series, but repeated at a later point in time. The test setup was identical and can be checked in the mentioned previous part.
The reason for running the test again was the fact that I was informed during (more...)
It's that time of the year again... I'll be speaking at the following events:
- SSWUG 2016 Fall Virtual Conference: On November 15th I'll do the geeky stuff that was rejected by DOAG this year, which is "Oracle Database Parallel Execution plans deep dive - understanding the internals of Parallel Execution plans". You should only attend this session if you already have a good understanding of serial execution plans.
This is the fourth part of this installment, comparing the performance consistency of the DBaaS cloud offering with a dedicated physical host. This time the previous read-only test was modified to be a 100% update read-write test. So every row read was updated in the following way:
begin loop for rec in ( select /*+ index(t_o) (more...)
This is just a short note that links to different articles on Alberto Dell'Era's blog. Alberto is a long time member of the OakTable and has published a number of posts I find very useful and therefore are linked here: