Friends Don't Let Friends Run Oracle on ZFS

I frequently get asked why I recommend against running Oracle DBMS on ZFS, and instead recommend using ASM. The filesystem v's ASM (or filesystem v's raw device) is a decision that people have had to make with databases for dozens of years. Over that time, in general, filesystem performance has…

#Tags: zfs, solaris, alignment, performance testing, xtremio, oracle

Flash testing tools - CrystalDiskMark

CrystalDiskMark is the type of tool I wouldn't even normally look at due to it's focus market, but one of our SE's asked about it last week, so... CrystalDiskMark is a tool you would normally see used on standalone hard disks/SSD, in particular on consumer focused websites like Toms…

#Tags: performance testing, xtremio, diskspd

Flash testing tools - Diskspd

Some time ago I wrote about Microsoft's storage performance testing tool SQLIO, with the conclusion that it was unsuitable for using with flash-based products as it wrote nothing but zeros, which will not be stored by flash but instead treated as if they were an UNMAP/TRIM request. It seems…

#Tags: performance testing, xtremio

ZFS and Intelligent Storage

It's been almost 10 years to the day since Sun Microsystems first released ZFS as a part of the Solaris 10 6/06 release. I worked for Sun at the time, and it was clear that ZFS was a revolution in file systems - but it was also very clear…

#Tags: solaris, zfs, xtremio

Vdbench Curve

Some time back I wrote about the relationship between Queue Depth, IOPS and Latency. This relationship can be particularly tricky when you're attempting to use performance testing tools to discover the characteristics of your storage. Most testing tools use the number of threads to control the workload they are generating,…

#Tags: xtremio, vdbench, performance testing

Partition Alignment - Solaris (SPARC)

For historic reasons, most modern disk drives and storage storage arrays claim to the host that they have a 512 byte block size which in fact they actually use something larger - normally 4k or 8k, but possibly even larger. If you send an IO to such a disk/array…

#Tags: solaris, xtremio, partition alignment, alignment