Oh dear god, corporate world has been getting to me. Starting to top-post by default, but occasionally catching myself in time... On Fri, 7 Nov 2014, Toby Corkindale wrote:
I have read stories of people spending lots of money on SD cards and finding none of them work, so am a bit nervous about doing this myself.
People buying lots of SD cards and none of them working? What's the one common thing amongst all those SD cards? The power supply.
Oh, one other thing -- I found that overclocking the raspberry pi caused me sd card corruption too, so if you're hitting issues, try going back to stock speeds.
Interesting. Might still be a power supply issue - more switching transients at higher clock speed. I had overclocked mine, and was using the original SD card I bought from element 14. I loaded munin onto it, and after a while, the latency was increasing to 1 second. I blew it away (not that SD cards support TRIM) and rebuilt it on btrfs, and the response time started increasing to 10 seconds after a few days (the graph almost looked log-linear, ie exponentially increasing latencies as it ran out of blocks to remap to) before it finally went read-only corrupt. The replacement card is working a lot better several months on. But I advocate putting munin on (turn copious logging and logfile sync etc off!) and monitoring disk latencies on all your systems. A Scary Devil Monk this morning showed his munin graphs of a 2 disk system pre- and post- a power failure. His disk whose latencies immediately went up by a factor of 10 turned out to have been a RMA replacement from only 9 months ago. -- Tim Connors