Notes to Self

Alex Sokolsky's Notes on Computers and Programming

1 April 2012

Sanity Checks

Nas4free seems to be most suited to my requirements, but samba there just crashes on me. In the meantime I am collecting network and hard drives throughput data on Windows.

HTPC runs Windows 7, NAS in this test runs Windows Vista. Both use Intel 82540EM PRO/1000 MT PCI NICs. Rate of data copying between two internal SATA2 drives on HTPC: windows copy dialog shows 120MB/sec in the beginning of the copy process. By the end it falls down to 87MB/sec. Writing to NAS (to 300MB Seagate HD) is done at a rate of 43MB/sec. Reading from NAS is done at a rate of 40MB/sec.

iperf bandwidth measurement between HTPC and another Windows PC is about 38MB/sec. Enabling jumbo frames (or changing their size from 4k to 9k) has no effect at all. I have no idea why the bandwidth is so low. I ordered a CAT6 cable and will try one more time bandwidth tests with two Windows PCs connected directly with no switch in between.

EDIT: later I determined that PCI NICs are the bottleneck!

Todo:

While waiting for the production version of firmware to materialize and production HBA to show up on my door step I was pondering over the hard drive use strategy. Should I go with RAIDZ? Given that the NAS cage can hold up to 4 drivers, and I do not plan to expand, my options are limited to RAIDZ and MIRROR. Here are two good articles on the subject. Decided! I will go with a mirror of two Barracuda Green 2TB drives.

Original post

2012-04-11-hardware.md

tags: software