I am using FancyCache on my windows system with 2 Intel 530 240 GB drives.
I have a separate deferred cache task set up for each drive.
Drive 0 is my system drive and Drive 2 is my data drive.
Drive 0 write amplification is around 4.5.
Drive 1 amplification is less than 1.
Block size is set at 4kb for each drive and deferred write is set to 60 seconds.
Is there a better block size to reduce amplification?
Note: Temp files and IE cache are located on Drive 1
Best way to reduce write amplification?
Re: Best way to reduce write amplification?
Hi,
This appears to be a 530 series firmware issue. Under certain conditions the 530 is prone to abnormally high write amplification. Moving Temp and IE off the SSD is a good step. Until (if ever) Intel comes up with a solution, your only hope is to prevent duplicate writes as much as possible by using a large Primo/Fancycache buffer. A longer timeout might also help, although this increases the risk of data loss in case of a crash. Of course Intel denies the problem and blames the OS. The trick appears to be to prevent small writes. Try monitoring your OS drive for any program periodically writing small amounts of data, such as logfiles.
Below part of a discussion on the Intel forum:
11. Re: Intel SSD 530 NAND Write Problem
HWR Jan 13, 2014 7:20 PM (in response to Besovski)
I am experiencing large NAND write consumption as well. I have a new intel 530 120 GB ssd with a fresh Windows 8.1 install. After the initial install period with many host writes I immediately noticed that the NAND writes continue to accumulate with little corresponding host writes.
As of now: 90.22 GB host writes and 227 GB NAND writes.
I have observed that I accumulate about 1 GB NAND writes per hour idle when basically the only writes are lastalive0.dat and lastalive1.dat updating at the usual 1 minute interval. If I disable these writes I can achieve several hours without NAND writes incrementing.
Running Photoshop CC with scratch disk on a separate HDD I accumulate 4 GB NAND writes per hour with only 0.25 GB host writes. This is sitting idle with no image open.
Basically, any small amount of host writes triggers a large amount of NAND writes.
This appears to be a 530 series firmware issue. Under certain conditions the 530 is prone to abnormally high write amplification. Moving Temp and IE off the SSD is a good step. Until (if ever) Intel comes up with a solution, your only hope is to prevent duplicate writes as much as possible by using a large Primo/Fancycache buffer. A longer timeout might also help, although this increases the risk of data loss in case of a crash. Of course Intel denies the problem and blames the OS. The trick appears to be to prevent small writes. Try monitoring your OS drive for any program periodically writing small amounts of data, such as logfiles.
Below part of a discussion on the Intel forum:
11. Re: Intel SSD 530 NAND Write Problem
HWR Jan 13, 2014 7:20 PM (in response to Besovski)
I am experiencing large NAND write consumption as well. I have a new intel 530 120 GB ssd with a fresh Windows 8.1 install. After the initial install period with many host writes I immediately noticed that the NAND writes continue to accumulate with little corresponding host writes.
As of now: 90.22 GB host writes and 227 GB NAND writes.
I have observed that I accumulate about 1 GB NAND writes per hour idle when basically the only writes are lastalive0.dat and lastalive1.dat updating at the usual 1 minute interval. If I disable these writes I can achieve several hours without NAND writes incrementing.
Running Photoshop CC with scratch disk on a separate HDD I accumulate 4 GB NAND writes per hour with only 0.25 GB host writes. This is sitting idle with no image open.
Basically, any small amount of host writes triggers a large amount of NAND writes.
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InquiringMind
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Re: Best way to reduce write amplification?
For temp files and browser caches, storing them on a ramdisk (such as Primo which should work well with FancyCache) may be better than relying on caching. Aside from that, the advice above seems sound.
Re: Best way to reduce write amplification?
Mistake in my first post, I am using PrimoCache rather than FancyCache, don't know what I was thinking. Also Drive 1 is my data drive.
I set lastalive0.dat and lastalive1.dat to not update as suggested by Bjameson to see if this helps.
Temp files and browser caches are on my second drive, also an Intel 530 240GB and at this time W/A is still less than 1 on that drive.
Just for the hell of it I am going to set my deferred write up to 8 hours on both drives for today to see what happens. I am backed up for this test.
My system drive W/A is around 4.6 now.
I will update you guys tomorrow.
I set lastalive0.dat and lastalive1.dat to not update as suggested by Bjameson to see if this helps.
Temp files and browser caches are on my second drive, also an Intel 530 240GB and at this time W/A is still less than 1 on that drive.
Just for the hell of it I am going to set my deferred write up to 8 hours on both drives for today to see what happens. I am backed up for this test.
My system drive W/A is around 4.6 now.
I will update you guys tomorrow.
Re: Best way to reduce write amplification?
Well this is what I came up with.
No host writes to the drive during this time.
1 Gb Nand writes each hour.
Flushed the buffer and re-booted.
time 8:43
3,183
time 10:43
3,185
Reboot
time 10:52
3,185
time 11:52
3,186
time 12:40
3,187
time 2:46
3,189
3,189 Total Nand Writes after reboot.
No host writes to the drive during this time.
1 Gb Nand writes each hour.
Flushed the buffer and re-booted.
time 8:43
3,183
time 10:43
3,185
Reboot
time 10:52
3,185
time 11:52
3,186
time 12:40
3,187
time 2:46
3,189
3,189 Total Nand Writes after reboot.