Hi, I got a WD 1T drive to use in a new machine for my dad. I didn't pay a huge amount of attention to the technical details when I purchased it other than it was SATA2, big, and the price was good. Here's the NewEgg link:
http://www.newegg.com/Product/Product.aspx?Item=N82E16822136490 I installed the drive, created some partitions and set off to put ext3 on it using just mke2fs -j /dev/sda3. The partitions gets written and everything works but when I started installing Gentoo on it I was getting some HUGE delays at times, such as when unpacking portage.latest.tar.bz. Basically the tar step would be rolling along and then the drive would literally appear to stop for 1 minute before proceeding. No CPU usage, the machine is alive in other terminals, but anything directed at the disk just seems dead. Sticking my ear on the drive it doesn't sound like the drive is doing anything. I was trying to determine what to do - I.e is this a bad drive, how to return it, etc. - and started reading the reviews at NewEgg. One guy using it with Linux had this to say: <QUOTE> 4KB physical sectors: KNOW WHAT YOU'RE DOING! Pros: Quiet, cool-running, big cache Cons: The 4KB physical sectors are a problem waiting to happen. If you misalign your partitions, disk performance can suffer. I ran benchmarks in Linux using a number of filesystems, and I found that with most filesystems, read performance and write performance with large files didn't suffer with misaligned partitions, but writes of many small files (unpacking a Linux kernel archive) could take several times as long with misaligned partitions as with aligned partitions. WD's advice about who needs to be concerned is overly simplistic, IMHO, and it's flat-out wrong for Linux, although it's probably accurate for 90% of buyers (those who run Windows or Mac OS and use their standard partitioning tools). If you're not part of that 90%, though, and if you don't fully understand this new technology and how to handle it, buy a drive with conventional 512-byte sectors! </QUOTE> Now, I don't mind getting a bit dirty learning to use this correctly but I'm wondering what that means in a practical sense. Reading the mke2fs man page the word 'sector' doesn't come up. It's my understanding the Linux 'blocks' are groups of sectors. True? If the disk must use 4K sectors then what - the smallest block has to be 4K and I'm using 1 sector per block? It seems that ext3 doesn't support anything larger than 4K? As a test I blew away all the partitions and made one huge 1 terabyte partition using ext3. I think tried untarring the portage snapshot and then deleting the directory where I put it a bunch of times. I get very different times each time I do this. untarring varies from 6 minutes 24 seconds to 10 minutes 25 seconds. Removing the directory varies from 3 seconds to 1 minute 22 seconds. Every time there is an apparent delay I just see the hard drive light turned on solid. That said as far as I know if I wait for things to complete the data is there but I haven't tested it extensively. Is this a bad drive or am I somehow using it incorrectly? Thanks, Mark gandalf TestMount # time tar xjf /mnt/TestMount/portage-latest.tar.bz2 -C /mnt/TestMount/usr real 6m24.736s user 0m9.969s sys 0m3.537s gandalf TestMount # time rm -rf /mnt/TestMount/usr/ real 0m3.229s user 0m0.110s sys 0m1.809s gandalf TestMount # mkdir usr gandalf TestMount # time tar xjf /mnt/TestMount/portage-latest.tar.bz2 -C /mnt/TestMount/usr real 7m50.193s user 0m8.647s sys 0m2.811s gandalf TestMount # time rm -rf /mnt/TestMount/usr/ real 0m3.234s user 0m0.119s sys 0m1.792s gandalf TestMount # mkdir usr gandalf TestMount # time tar xjf /mnt/TestMount/portage-latest.tar.bz2 -C /mnt/TestMount/usr real 10m25.926s user 0m8.645s sys 0m2.765s gandalf TestMount # time rm -rf /mnt/TestMount/usr/ real 1m22.330s user 0m0.124s sys 0m1.810s gandalf TestMount # mkdir usr gandalf TestMount # time tar xjf /mnt/TestMount/portage-latest.tar.bz2 -C /mnt/TestMount/usr real 8m12.307s user 0m8.463s sys 0m2.708s gandalf TestMount # time rm -rf /mnt/TestMount/usr/ real 0m29.517s user 0m0.114s sys 0m1.810s gandalf TestMount # gandalf ~ # hdparm -tT /dev/sdb /dev/sdb: Timing cached reads: 11362 MB in 2.00 seconds = 5684.46 MB/sec Timing buffered disk reads: 314 MB in 3.00 seconds = 104.64 MB/sec gandalf ~ #
