<div dir="ltr">I agree with the comments in favor of SSDs in general, but I'm not surprised by John's finding that they don't magically solve the problems of running out of RAM. I think the issue is that the read/write speeds are slower than for RAM and the physical distance from the CPU is greater (perhaps also with less throughput in that connection). Allan Hicks knows more about this stuff but he's out to sea right now. In theory, the partitioning of the calculations to have some elements written to disk and others to RAM might also make the computations less efficient, but probably only Dave could know whether that's true.</div>
<div class="gmail_extra"><br><br><div class="gmail_quote">On Fri, Sep 20, 2013 at 11:17 AM, John Sibert <span dir="ltr"><<a href="mailto:sibert@hawaii.edu" target="_blank">sibert@hawaii.edu</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
Generally I love SSDs. My new laptop boots up from power on to login screen in about 12 seconds. I/O is usually really fast, but it is not nearly as fast as RAM. Below are timings to do 10 function evaluations with (1) writing temporary gradient data to SSD and (2) keeping the the same data in RAM. It is probably faster than writing to a spinning disk, but I no longer have a computer with one of those to test it.<br>
<br>
(1) Writing to SSD<br>
$ time ~/movemod/25/tpl/tagest -gbs 500000 -cbs 500000 -maxfn 10 -est<br>
real 2m4.024s<br>
user 1m38.994s<br>
sys 0m23.509s<br>
<br>
-rwxrwxr-x 1 jsibert jsibert 62000000 Sep 20 08:04 cmpdiff.tmp*<br>
-rwxrwxr-x 1 jsibert jsibert 175440000 Sep 20 08:04 gradfil1.tmp*<br>
-rwxrwxr-x 1 jsibert jsibert 0 Sep 20 08:03 gradfil2.tmp*<br>
-rwxrwxr-x 1 jsibert jsibert 0 Sep 20 08:03 varssave.tmp*<br>
<br>
<br>
(2) retaining in RAM<br>
$ time ~/movemod/25/tpl/tagest -maxfn 10 -est<br>
real 1m35.423s<br>
user 1m34.906s<br>
sys 0m0.124s<br>
<br>
-rwxrwxr-x 1 jsibert jsibert 0 Sep 20 08:05 cmpdiff.tmp*<br>
-rwxrwxr-x 1 jsibert jsibert 0 Sep 20 08:05 gradfil1.tmp*<br>
-rwxrwxr-x 1 jsibert jsibert 0 Sep 20 08:05 gradfil2.tmp*<br>
-rwxrwxr-x 1 jsibert jsibert 0 Sep 20 08:05 varssave.tmp*<div class="im HOEnZb"><br>
<br>
<br>
John Sibert<br>
Emeritus Researcher, SOEST<br>
University of Hawaii at Manoa<br>
Honolulu HI (GMT-10)<br>
<a href="tel:808-294-3842" value="+18082943842" target="_blank">808-294-3842</a><br>
<br>
Visit the ADMB project <a href="http://admb-project.org/" target="_blank">http://admb-project.org/</a><br>
<br></div><div class="HOEnZb"><div class="h5">
On 09/19/2013 03:35 PM, Mark Maunder wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
I don't have an application on mind. Just buying some new modeling machines and working out what is important.<br>
<br>
Regards,<br>
<br>
Mark<br>
IATTC<br>
<br>
On Sep 19, 2013, at 5:36 PM, "John Sibert" <<a href="mailto:sibert@hawaii.edu" target="_blank">sibert@hawaii.edu</a>> wrote:<br>
<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
I'm not sure whether you are asking about swap memory controlled by the operating system or to writing ADMB gradient data to the disk. The former is almost always a mistake. The latter would be interesting to test. I have an old linux laptop with a brand new SSD. If you send me your tpl and dat files, I could run some tests.<br>
Cheers,<br>
John<br>
<br>
John Sibert<br>
Emeritus Researcher, SOEST<br>
University of Hawaii at Manoa<br>
Honolulu HI (GMT-10)<br>
<a href="tel:808-294-3842" value="+18082943842" target="_blank">808-294-3842</a><br>
<br>
Visit the ADMB project <a href="http://admb-project.org/" target="_blank">http://admb-project.org/</a><br>
<br>
On 09/19/2013 12:11 PM, Mark Maunder wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
Has anyone tried to run a big ADMB model that swaps memory to the hard drive with a solid state drive? Does this perform reasonably or is it still really slow?<br>
<br>
*From:*<a href="mailto:users-bounces@admb-project.org" target="_blank">users-bounces@admb-<u></u>project.org</a> [mailto:<a href="mailto:users-bounces@admb-project.org" target="_blank">users-bounces@admb-<u></u>project.org</a>] *On Behalf Of *Mollie Brooks<br>
*Sent:* Thursday, September 19, 2013 1:43 PM<br>
*To:* <a href="mailto:users@admb-project.org" target="_blank">users@admb-project.org</a> Group<br>
*Subject:* [ADMB Users] dnbinom<br>
<br>
Hi ADMB users,<br>
<br>
Has anyone besides me used the dnbinom function in their code?<br>
<br>
There's a little discussion about the possibility of reparameterizing it, but we don't want to disrupt too many people.<br>
<br>
Thanks,<br>
<br>
Mollie<br>
<br>
------------------------<br>
<br>
Mollie Brooks, PhD<br>
Postdoctoral Researcher, Population Ecology Research Group <a href="http://www.popecol.org" target="_blank">http://www.popecol.org</a> <<a href="http://www.popecol.org" target="_blank">http://www.popecol.org</a>><br>
Institute of Evolutionary Biology & Environmental Studies, University of Zürich<br>
<br>
<br>
<br>
______________________________<u></u>_________________<br>
Users mailing list<br>
<a href="mailto:Users@admb-project.org" target="_blank">Users@admb-project.org</a><br>
<a href="http://lists.admb-project.org/mailman/listinfo/users" target="_blank">http://lists.admb-project.org/<u></u>mailman/listinfo/users</a><br>
</blockquote>
<br>
</blockquote></blockquote>
<br>
<br>
______________________________<u></u>_________________<br>
Users mailing list<br>
<a href="mailto:Users@admb-project.org" target="_blank">Users@admb-project.org</a><br>
<a href="http://lists.admb-project.org/mailman/listinfo/users" target="_blank">http://lists.admb-project.org/<u></u>mailman/listinfo/users</a><br>
</div></div></blockquote></div><br></div>