Hardware

The hardware notes in this archive cover 2007 to 2012, and they are dominated by one transition: the arrival of consumer and small-business solid-state storage, and the discovery that it behaved nothing like the mechanical drives everyone's assumptions were built on. Around that sit direct-attached storage enclosures, motherboard faults, processor choices and the performance counters used to work out which component was actually responsible for a slow machine.

Why storage dominates this section

Between 2008 and 2012 solid-state drives went from an expensive curiosity to the default answer for anything latency-sensitive, and the early ones were genuinely troublesome. Firmware was immature, the operating system did not yet understand the medium, and the failure modes were unfamiliar. The archive tracks that year by year: early low-cost drive announcements and the case for putting databases on flash, then how to secure erase (reset) an Intel solid-state drive once it became clear that a drive whose blocks had all been written once was much slower than a fresh one, then the arrival of firmware and TRIM support for Windows 7, and finally fixing an SSD freezing on Windows 7, which is the mature form of the problem — a drive that stalls for seconds under a power-management setting rather than a drive that is simply worn.

Underneath all of it is the measurement question, and that is what makes high average disk queue length and finding the cause the most durable note in this section. The counter it uses still exists, and its central point — that a queue length is uninterpretable without knowing how many physical devices are serving it — is as true of a modern array as it was of a 2008 RAID set. Read next to the SSD-freezing note, it is a small worked example of separating a device problem from a driver problem from a load problem.

The remaining notes are the ordinary business of running physical machines: direct-attached enclosures and their benchmarks, a motherboard that produced an out-of-range video signal on a fresh Windows 2003 install, a processor that turned out to be a poor match for the workload it was bought for, and — filed here because it is a hardware note in everything but name — installing Jolicloud on an Asus T91 or T91MT, a netbook whose graphics chipset defeated its own graphical installer.

What has changed since

Almost every specific instruction in this section is obsolete. The drives are gone, the firmware versions no longer exist, and the vendor tools that shipped with them have been replaced several times over. Secure erase in particular should not be performed from a fifteen-year-old procedure: the authoritative current guidance on sanitising storage media is NIST Special Publication 800-88 Revision 1, which distinguishes clearing, purging and destroying, and which covers flash media explicitly.

What survives is the reasoning about measurement, and one durable warning: flash storage fails in ways that look like software faults. A stall that presents as an unresponsive application, a filesystem that appears corrupt, a machine that seems to have a driver problem — all three appear in this section with a storage cause. Windows-side diagnostic material has moved to Microsoft's Windows Server troubleshooting guidance.

The disk-performance notes overlap with Windows and Server, since the counters and the power-management settings involved are operating-system features.

Notes filed under Hardware

Linked titles are restored pages. Plain titles are a record of what was published at that URL; the full corpus is indexed in the complete post archive.

• 22 September 2007 — Asus M2A-VM and Windows Vista
• 18 March 2008 — Dell PowerVault MD1000 Direct Attached Storage
• 24 March 2008 — Dell DAS MD1000 Benchmarks
• 16 July 2008 — RiData Announces Three New Low-Cost SSDs
• 25 August 2008 — Intel Board SE7221BA1-E: Signal Out of Range With a Fresh Windows 2003 Install
• 1 September 2008 — Nimble Data With Solid State Drives
• 12 September 2008 — High Avg Disk Queue Length and finding the Cause
• 30 June 2009 — How to Secure Erase (reset) an Intel Solid State Drive (SSD)
• 15 September 2009 — Core i7 860 Is Slow for Ripping Music and Managing Photos
• 26 October 2009 — Intel Releases SSD Firmware and TRIM Tool for Windows 7
• 13 November 2010 — Installing Jolicloud on an Asus T91 or T91MT
• 14 October 2012 — Fixing an SSD Freezing on Windows 7