My Raspberry PI

Out the box the Raspberry PI comes with a ARM1176JZFS Core (armv6 with hard float aka armhf arch) running at 700 Mhz as part of the Broadcom SoC. Additionally the memory frequency is also limited. In recent firmwares however… tinkerers have had the ability to “overclock” the Raspberry PI to squeeze some extra juice out of it. Mine’s currently running at 1Ghz at a solid 48C temperature when under load. So the first question that springs to mind is… why doesn’t everyone overclock their Raspberry PI? Well… there have been (well founded) reports of SD card corruption, heat/power issues and instability. The idea of this post is to show the user how to safety squeeze every last bit, cycle and IOP out of their PI safely’ish and without being an astrophysicist. Read on for the know-how. Continue reading

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It’s a bit of a random thing you’d think, but recently I had an issue where one of my servers would keep dieing when under abnormal load… So I thought, how can i replicate this in a lab environment… So I wrote a tiny bash script (that you can just paste into a terminal) that will max out each “thread” of the CPU until you kill the processes or reboot… Useful for stress-testing or burning in a CPU…

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Following on from my previous post regarding AFP and iSCSI benchmarks i’ve decided (after many requests) to post a few raw benchmarks of the system gathered by bonnie++, the environment is as follows:

CPU: Athlon 64 3700+
RAM: 2gb DDR400
Controllers: 2x SATA-II and 1x SATA-I
Hard Drives: 7x Samsung 2tb Spinpoint F3 5600 RPM
OS: NexentaStor 3
ZFS Config: Standard raidz1 with dedup=off and compression=off

So I gathered a few results… after some annoying results I found a bottleneck in my system on 1 of the drives that seemed to bring the benchmark result down greatly, however once this was worked out I acheived the following: Continue reading

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UPDATED WITH BOTH iSCSI & AFP RESULTS

I’ve recently setup a ZFS raidz with 7 disks using NexentaStor, natively this doesn’t come with AFP, but I managed to get a package and get this all working (which i’ll demo in an upcoming tutorial), one thing i noticed however is that I could never find any benchmarks that tested the general use of a NAS… i.e. using CIFS or AFP over a network to another machine and testing performance. There are literally 0 AFP benchmarks for NexentaStor due to its non-native support. So here it is

Test Environment:

NAS: 7 SAMSUNG Spinspoint F3 2tb Hard drives connected via SATA & SATA-II, in a ZFS raidz running on NexentaStor 3
Network: 1000BaseT Gigabit LAN
Test Machine: MacMini with 1gb memory (disk tests are cached in memory for speed) running XBench to benchmark
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