On Jan 21, 2016, at 12:35 AM, Rolly Ng <[email protected]> wrote: > My server has total of 144GB RAM and 8x C2050. These cards have 3GB memory > each, so there are 24 GB of video RAM. If I compile px-gpu.x with the option > "--with-pinned-mem", does it lock 24GB of system memory out of 144 GB? and I > will have 120 GB system RAM left?
Not exaclty, it "locks" a portion of the CPU memory but it depends by the input and not by the amount of memory on the GPU. It should be less but it depends by the input case (since specific data structures are "pinned", others are not). By default, very little data structures that are transferred to the GPU are already allocated as page-locked. Give it a try, if you calculation starts a complete few SCF iterations then more likely will run until the very end. You may experience a bit (but a very little) increase in performance. But if too much memory is pinned, the system can get slow. It is not intuitive why but it can happen. HTH -- Mr. Filippo SPIGA, M.Sc. Quantum ESPRESSO Foundation http://www.quantum-espresso.org ~ skype: filippo.spiga ***** Disclaimer: "Please note this message and any attachments are CONFIDENTIAL and may be privileged or otherwise protected from disclosure. The contents are not to be disclosed to anyone other than the addressee. Unauthorized recipients are requested to preserve this confidentiality and to advise the sender immediately of any error in transmission." _______________________________________________ Pw_forum mailing list [email protected] http://pwscf.org/mailman/listinfo/pw_forum
