April 18, 2014

Modeling MySQL Capacity by Measuring Resource Consumptions

There are many angles you can look at the system to predict in performance, the model baron has published for example is good for measuring scalability of the system as concurrency growths. In many cases however we’re facing a need to answer a question how much load a given system can handle when load is […]

OpenSSL heartbleed CVE-2014-0160 – Data leaks make my heart bleed

The heartbleed bug was introduced in OpenSSL 1.0.1 and is present in 1.0.1 1.0.1a 1.0.1b 1.0.1c 1.0.1d 1.0.1e 1.0.1f The bug is not present in 1.0.1g, nor is it present in the 1.0.0 branch nor the 0.9.8 branch of OpenSSL some sources report 1.0.2-beta is also affected by this bug at the time of writing, […]

Aligning IO on a hard disk RAID – the Benchmarks

In the first part of this article I have showed how I align IO, now I want to share results of the benchmark that I have been running to see how much benefit can we get from a proper IO alignment on a 4-disk RAID1+0 with 64k stripe element. I haven’t been running any benchmarks […]

FlashCache: more benchmarks

Previously I covered simple case with FlashCache, when data fits into cache partitions, now I am trying to test when data is bigger than cache. But before test setup let me address some concern (which I also had). Intel X25-M has a write cache which is not battery backuped, so there is suspect you may […]

RAID vs SSD vs FusionIO

In benchmarks passion (see my two previous posts) I managed to setup all three devices (RAID was on board; Intel X25-E SSD connected to HighPoint controller, FusionIO card) on our working horse Dell PowerEdge R900 (btw, to do that I had to switch from CentOS 5.2 to Ubuntu 8.10, as CentOS was not able to […]