February 20, 2010
WD hdd: Advanced Format
I'm changing my main hdd from 1tb Seagate (see previous post about seagate problems) to 1tb WD green.
I've got new 1Tb WD HDD formatted with "Advanced Format". I'm going to use it as main hdd after cloning partitions from current Seagate. First thing I made is just cloned whole hdd and restarted from new one. Hmm, performance is REALLY BAD. Let's read the manual...
The instruction on new hdd says: use WD Align utility if you use cloning software. No details. Just does some magic to your hdd.
The thing that was not said almost anywhere on wdc.com or all the other sites who just repost text from wdc: when to run wd align utility?
The purpose of wd align tools is to align partitions on the border of 4kb (usually size is 512b) physical sectors (ntfs cluster is aligned in this case and the overall performance is better). HDD emulates more accurate 512b-step addressing, but this is very slow, because NTFS uses 4k clusters that usually (3/4 probability :-), with default winxp partitioning increases to 100%, because of some strange reserve of 63 sectors before first partition) breaks to 2 physical sectors. The problem is that to "align" 30Gb partition (not even half of whole 1Tb hdd space) filled to 25Gb with data, it requires more than an hour! If you have already cloned partitions with data filled for example 500Gb (50% of whole disk), it takes ~20 hours. I had ~750 Gb of data. Not way to align in a reasonable time.
The right way is to make empty partitions before cloning your data to new hdd, align it with "paragon wd align" (~10 seconds for 500Gb partition, pretty fast), and after that clone your data using for example Norton Ghost. The only trick is to know sizes of target partitions. To be sure your data fits there well, adjust free space to be more than 3-5%. And remember that not all data cloning software defragments target partition, some use "sector to sector" copy (only non-empty sectors of course).
Good luck with Advanced Format disks! Some say that soon all of HDDs will be made using AF (the 4k sector size increase disk space usage, because require less low-level intersector markers which require some space).
Surprise
I've got new 1Tb WD HDD formatted with "Advanced Format". I'm going to use it as main hdd after cloning partitions from current Seagate. First thing I made is just cloned whole hdd and restarted from new one. Hmm, performance is REALLY BAD. Let's read the manual...
Details
The instruction on new hdd says: use WD Align utility if you use cloning software. No details. Just does some magic to your hdd.
The thing that was not said almost anywhere on wdc.com or all the other sites who just repost text from wdc: when to run wd align utility?
Problem: aligning takes huge time.
The purpose of wd align tools is to align partitions on the border of 4kb (usually size is 512b) physical sectors (ntfs cluster is aligned in this case and the overall performance is better). HDD emulates more accurate 512b-step addressing, but this is very slow, because NTFS uses 4k clusters that usually (3/4 probability :-), with default winxp partitioning increases to 100%, because of some strange reserve of 63 sectors before first partition) breaks to 2 physical sectors. The problem is that to "align" 30Gb partition (not even half of whole 1Tb hdd space) filled to 25Gb with data, it requires more than an hour! If you have already cloned partitions with data filled for example 500Gb (50% of whole disk), it takes ~20 hours. I had ~750 Gb of data. Not way to align in a reasonable time.
Solution:
The right way is to make empty partitions before cloning your data to new hdd, align it with "paragon wd align" (~10 seconds for 500Gb partition, pretty fast), and after that clone your data using for example Norton Ghost. The only trick is to know sizes of target partitions. To be sure your data fits there well, adjust free space to be more than 3-5%. And remember that not all data cloning software defragments target partition, some use "sector to sector" copy (only non-empty sectors of course).
Good luck with Advanced Format disks! Some say that soon all of HDDs will be made using AF (the 4k sector size increase disk space usage, because require less low-level intersector markers which require some space).
Labels: advanced format, hdd, sector size, wd, wd align, winxp
