1.5 TB WD Green 64 MB Cache - $109.99

Western Digital Caviar Green WD15EARS 1.5TB 64MB Cache SATA 3.0Gb/s 3.5" Internal Hard Drive

The 64 MB cache should make this one fast drive, even given its slower 'green' rotational speed.  Appropriate for a parity drive, perhaps?

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That's also one of the EARS drives that makes use of the new advanced format of 4KB sectors instead of 512B.  If anyone gets one, please report what the formated size of the drive is to see if the actual space available is larger as expected with these drives.  I don't think anyone has actually confirmed it yet. 

I'd like to know the parity performance of the drive as well 

I'd like to know the parity performance of the drive as well 

1. When initially calculating parity, the parity drive is being written only(I do not think it is being read, as there is no need)

2. When subsequently checking parity, the drive is being read only, rotation speed is not as much an issue as long as it can keep the bus to the CPU filled with data. (here the larger buffer may help)

3. When writing files to a data drive, the parity drive is being read, then written, then read, then written.... with disk rotations between reading and writing each stripe on the disk.  Here, the 5400 RPM will make any parity drive slower than a 7200 RPM drive.

Three different modes of operation to measure, all involving the parity drive.  Whoever measures the performance needs to perform several tests.  It might work faster when pressing the "Check" button (read only), but slower when storing a new movie to the array (read/write interleaved)

The final formatted size is identical to the EADS drive.  The increase of space gained from the efficiency of 4K sectors is used by an expanded ECC that should give greater reliability (although it is not reflected in the specs yet).

The WD specs show them identical in user space.

I also saw in one forum, but don't have the link, where someone installed each under Windows, and formatted them, and although the RAW space was larger for the EARS, the area taken up by formatting was larger, leaving the EXACT same space for the end user.

Regarding performance....I can only say comparative performance in their system. ie, On my system, on a full parity check I get a rate of 47860K/sec. Any number they give me doesn't really give me an indication unless they can tell me what they were coming from and whether it was faster/slower than that for them.

so has anyone actually got these running in their UNRAID server?

looking to buy some 1.5TB drives soon and wanted to ensure I was not buying something which is incompatible.

thanks!

I'm using them in my server I just built.  I have been sorting through gobs of old data and moving files over  to the unraid box a little bit each day.  Getting 70+ MB/s consistently going to/from my windows machine with no parity checking yet.  It might be capable of faster but my windows machine doesn't exactly have fast drives and is set up in raid 5 which slows it's drives down.

That's also one of the EARS drives that makes use of the new advanced format of 4KB sectors instead of 512B.  If anyone gets one, please report what the formated size of the drive is to see if the actual space available is larger as expected with these drives.  I don't think anyone has actually confirmed it yet. 

1.465 TB formatted

That's also one of the EARS drives that makes use of the new advanced format of 4KB sectors instead of 512B.  If anyone gets one, please report what the formated size of the drive is to see if the actual space available is larger as expected with these drives.  I don't think anyone has actually confirmed it yet. 

 

1.465 TB formatted

Could you possibly get the geometry?

fdisk -l /dev/sdX

where sdX = the device of the EARS drive in your array

pretty sure the WD marketing team would be the first people to tell us if they could fit more data.... they are operating in 512B emulation mode so I'm guessing they don't look much different to any other drive.

That's also one of the EARS drives that makes use of the new advanced format of 4KB sectors instead of 512B.  If anyone gets one, please report what the formated size of the drive is to see if the actual space available is larger as expected with these drives.  I don't think anyone has actually confirmed it yet. 

 

1.465 TB formatted

Could you possibly get the geometry?

fdisk -l /dev/sdX

 

where sdX = the device of the EARS drive in your array

root@Tower:~# fdisk -l /dev/sdb

Disk /dev/sdb: 1500.3 GB, 1500301910016 bytes

1 heads, 63 sectors/track, 46512336 cylinders

Units = cylinders of 63 * 512 = 32256 bytes

Disk identifier: 0x00000000

  Device Boot      Start        End      Blocks  Id  System

/dev/sdb1              2    46512336  1465138552+  83  Linux

Partition 1 does not end on cylinder boundary.

root@Tower:~#