Mac Pro 12 Core (24 treads) and only 8 working, others saying Wait for shared Memory
Questions and Answers :
Macintosh :
Mac Pro 12 Core (24 treads) and only 8 working, others saying Wait for shared Memory
Message board moderation
| Author | Message |
|---|---|
 Luigi LAPLACE Send message Joined: 10 Feb 12 Posts: 2 Credit: 452,420 RAC: 0 
|
Hello everybody ! I have a problem with Boinc everytime I launch it, only 8 tasks are running together + the openCL one. But, I'm using a 12 core Mac Pro (24 tread usable) with 24 GB of RAM and a GTX680. I don't undrestand because it doesn't use all my RAM. Does anyone have an idea ? ID: 1829210 ·  |
Jord  Send message Joined: 9 Jun 99 Posts: 15184 Credit: 4,362,181 RAC: 3 
|
Having loads of memory doesn't mean you have enough shared memory. From this BOINC FAQ: BOINC science applications use shared memory to communicate with the core client, and a certain amount is reserved for each current task, whether running or waiting. The default configuration of a multi-CPU Mac (regardless of how much RAM is installed) is sometimes inadequate to support several projects at once. If you get this error message, which is usually followed by a “Couldn't start or resume: -144†error in the current computation, it may help to set your BOINC general preference “Leave applications in memory while suspended?†to no; however, the problem will probably just become less frequent rather than being solved, and moreover some projects’ applications, those that save checkpoints infrequently (or erratically), may not take well to this setting. A better solution is available—if you don’t mind reconfiguring your system’s kernel a little. The method, accompanied by a more detailed description of the issue, is outlined in Configuring Shared Memory on Mac OS X from Spy Hill Research (hosts of the BOINC Pirates@home project). It involves creating a text file “/etc/sysctl.conf†that contains the following commands: kern.sysv.shmmax=16777216 kern.sysv.shmmin=1 kern.sysv.shmmni=128 kern.sysv.shmseg=32 kern.sysv.shmall=4096 and rebooting the computer. This will quadruple the default allocation of shared memory. Note that the problem may manifest with slightly different error messages: “Can't create shared memory: system shmat†followed by “Couldn't start or resume: -146â€. ID: 1829214 · |
|
Luigi LAPLACE Send message Joined: 10 Feb 12 Posts: 2 Credit: 452,420 RAC: 0
|
Thank you, I found it last night, but, thank you so much ! ID: 1829284 · |
©2025 University of California
SETI@home and Astropulse are funded by grants from the National Science Foundation, NASA, and donations from SETI@home volunteers. AstroPulse is funded in part by the NSF through grant AST-0307956.