[Dovecot] SSD drives are really fast running Dovecot

[Marc Perkel]

On 1/12/2011 9:58 AM, Rick Romero wrote:
> Quoting Marc Perkel <marc at perkel.com>:
>>> I just replaced my drives for Dovecot using Maildir format with a
>> > pair of Solid State Drives (SSD) in a raid 0 configuration. It's
>> > really really fast. Kind of expensive but it's like getting 20x the
>> > speed for 20x the price. I think the big gain is in the 0 seek time.
>> >
>> > Here's what I bought.
>> >
>> > Crucial RealSSD C300 CTFDDAC256MAG-1G1 2.5" 256GB SATA III MLC
>> > Internal Solid State Drive (SSD)
>> > <http://www.newegg.com/Product/Product.aspx?Item=N82E16820148349>
>> >
>> >    *   2.5"
>> >    *   256GB
>> >    *   SATA III
>> >
>> >    * *Sequential Access - Read:* 355MB/sec (SATA 6Gb/s) 265MB/sec 
>> (SATA
>> >      3Gb/s)
>> >    * *Sequential Access - Write:* 215MB/sec (SATA 6Gb/s) 215MB/sec
>> >      (SATA 3Gb/s)
>> >    * *Power Consumption (Active):* 2.1W READ, 4.3W WRITE
>> >    * *Power Consumption (Idle):* 0.094W
>> >
>> > Running it on an Asus motherboard that supports SATA III - 6 core AMD
>> > CPU and 16 gigs of ram. Might be slightly off topic but this server
>> > screams!
> Hey Marc,
>
> Just for testing purposes, what does a dd speed test give you?
>
> http://it.toolbox.com/blogs/database-soup/testing-disk-speed-the-dd-test-31069 
>
> IMHO, the key part is exceeding the RAM size, but for a "closer to
> Maildir" comparison, a decent file size that exceeds the drive cache is
> good too..
>
> Rick
>

Looks like a good test. Here's my results.

time sh -c "dd if=/dev/zero of=ddfile bs=8k count=2000000 && sync"

2000000+0 records in
2000000+0 records out
16384000000 bytes (16 GB) copied, 55.403 s, 296 MB/s

real    1m4.738s
user    0m0.336s
sys     0m20.199s