<div dir="ltr"><br><div class="gmail_extra"><br><br><div class="gmail_quote">On Sun, Dec 30, 2012 at 6:26 AM, Dan Shimshoni <span dir="ltr"><<a href="mailto:danshimsh@gmail.com" target="_blank">danshimsh@gmail.com</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">Hi,<br>
<br>
2 Questions about SSD drives:<br>
<br>
First, I would appreciate of someone who has SSD disk will<br>
run<br>
hdparm -t /dev/sda<br>
and post the results here. (In the spirit of the recent thread about<br>
HW for linux).<br>
<br>
I have<br>
/dev/sda:<br>
Timing buffered disk reads: 586 MB in 3.01 seconds = 194.68 MB/sec<br>
And it interests me to compare results<br>
<br>
<br></blockquote><div><br></div><div>An almost two years old Intel X25-E :<br><br># hdparm -t /dev/sda<br><br>/dev/sda:<br> Timing buffered disk reads: 714 MB in 3.01 seconds = 237.40 MB/sec<br><br></div><div># uname -a<br>
Linux matrix 3.6.2-gentoo #1 SMP PREEMPT Sun Oct 21 22:49:01 IST 2012 x86_64 AMD Phenom(tm) II X4 955 Processor AuthenticAMD GNU/Linux<br><br></div><div> </div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">
Does a result of, let's say, 400 MB/sec, which is double speed comparing the<br>
above result, will boost a task of building a linux kernel (on a dual<br>
core machine)<br>
in about 1.5 or 2?<br>
<br></blockquote><div><br></div><div>I really don't think so. SSDs (IMHO) makes computer much faster due to the VERY low seek time - the time it takes you to get a block. Compare 10-20ms with ~0.1ms. A regular hard drive simply wastes a lost of time seeking the data, instead of... reading it :) When you work with a lot of files, getting to the file fast makes a tremendous difference. This is similar to the reason why browsing websites which are close to you network-wise is much faster - even though the bandwidth you have is the same - the client/server latency due to the network affects the time it takes you to negotiate (compare to 'seek') with the server the content you want. The more objects you want, the higher the latency, the slower the site will load. This is why using CDNs and reducing the number of HTTP requests (e.g. by using CSS Sprites) - help a lot in speeding websites.<br>
</div><div> </div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">
Second question:<br>
I must admit that I am a newbie with SSD, so this question might seem<br>
obvoious to others:<br>
I saw that inner SSD disks, which are sold in stores like KSP/Ivory,<br>
are in laptop form factor (2.5'').<br>
<br></blockquote><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">
Is there some reason that there are no inner 3.5'' disks for Desktops (there<br>
are extenal SSD which can be , so I believe, used with desktops) ?<br></blockquote><div><br>Hard Drives have a reason to be large - they have a platter that
occupies space. If you reduce the platter size, you need to enlarge the
density, or add more platters - which adds thickness, noise, heat, and
lowers your MTBF. Electronics nowdays are small and doesn't need all
that... There's no point in making a large chassis just for the purpose
of a large chassis...<br><br> </div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">
Is there something which prevent us from connecting 2.5'' inner SSD to<br>
a desktop (I mean STAT2- based or SATA3-based) ?<br>
<br></blockquote><div><br></div><div>Not really. The SATA is the same. Your only issue is fixating the drive to your PC chassis. Some computer cases have a special place for 2.5" drives for SSD (like my Antec 1200). Alternatively there are 3.5"->2.5" adapters. But learn from someone who made a mistake (me ;)) - check before you buy that they're compatible with the screws location of the SSD.<br>
</div><div><br></div><div>HTH,<br><br></div><div>-- Shimi<br></div></div><br></div></div>