A Crucial M4 with a non-TRIM-capable OS?

mikeymikec

Lifer
May 19, 2011
21,133
16,336
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I've made the mistake of forgetting to consider my OS choice wrt TRIM for my new server build (Internet connected, web/ftp/mail services running off it).

I have Win2k8 Server. 2k8 R2 is TRIM-capable apparently, but not the former.

As I understand it, the M4's garbage collection feature should rule out the 'used write performance penalty', but a non-TRIM-capable OS will cause more write requests to occur, presumably 'wearing down the drive' sooner than a TRIM-capable OS.

Is my understanding correct? I don't really have the budget to buy a copy of R2, so as I see it, my choices are:

1 - Run the SSD with 2k8.
2 - Use the SSD for something else and get a HDD for 2k8.

I hoped to use an SSD for the server as it sits in my front room so noise level is a concern as is power usage.
 

dmoney1980

Platinum Member
Jan 17, 2008
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not recommended based on Anand's review of the m4

What does all of this mean? It means that it's physically possible for the m4, if hammered with a particularly gruesome workload (or a mostly naughty workload for a longer period of time), to end up in a pretty poor performance state. I had the same complaint about the C300 if you'll remember from last year. If you're running an OS without TRIM support, then the m4 is a definite pass. Even with TRIM enabled and a sufficiently random workload, you'll want to skip the m4 as well.

source: http://www.anandtech.com/show/4253/the-crucial-m4-micron-c400-ssd-review/2

of course this was based on initial firmware, below is what they said during the review of the latest firmware

The bigger concern is running the m4 in an OS without official TRIM support (e.g. Mac OS X) where you could find yourself in a particularly bad situation over a long period of time. Even then, it's obvious that sequential write passes over used LBAs cleans the drive up fairly well. Chances are that a standard desktop workload in a TRIM-free OS would be fine over the long run. If not, some sequential writes to any free space would do the trick (e.g. copying a large video file then deleting it).

http://www.anandtech.com/show/4712/the-crucial-m4-ssd-update-faster-with-fw0009/6

all of this may not apply to you if you just plan on running the OS on it and not much else. If thats the case then I think you'll be fine
 
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Emulex

Diamond Member
Jan 28, 2001
9,759
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Trim doesn't really matter as much as over provisioning. Intel 710 can go up to 50% (320 gb nand intel 320 -> 160gb with settings).

Longevity and long steady state performance gains are huge. Now Keep in mind that if your idea of long runs are 1 minute of ETL, you may not see gains, most benchmarks are hours of steady writes following by a serious thrashing.

For most folks this is unrealistic, even in SMB where you are doing bursty traffic. Caches on the raid controllers can even dampen this out.

Hell on my 9260-8i with fastpath, I can't even get a 6 or 8 disk raid-10 setup over QD 1 because the drives are so damn fast so you never get into the sweet spot for long.

SQL server - for instance with monstrous ram (8gb rdimm ecc are $60 still, a dual quad core can hold 144gb) can load an entire database into ram and it will never ever read the same sector once its in the main cache so read-ahead is moot.

90% of the writes are focused to tempdb file and of course the LOG FILE. However most folks have realized that modern 15K 146gb 2.5" SFF drives in raid 1+0 can easily outgun ssd and reduce the writes to your ssd massively since those can go through the 1gb FLASH BACK WRITE CACHE to the log hard drives.

So you then have tempdb's and that's about it.

25% OP and no trim would probably give you a very long life.

If you cannot afford 25% OP, give it what you can afford. Or in the example above, get some old sas drives for log writes to reduce wear.
 

Cerb

Elite Member
Aug 26, 2000
17,484
33
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You're worrying too much. The kind of loads that might be able to screw with the M4 are not going to much affect a file server (or most desktops, not running insane stress-testing software).

With TRIM, you will get over-provisioning and free space to wear-level. Without TRIM, you will just have the over-provisioning. In some workloads, it can increase write amplification. Thus, enterprise drives have more over-provisioning. Unless file server is code a torrent box, you won't ever even get close to needing to worry about it.