X-Git-Url: https://git.openpandora.org/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=Documentation%2FIPMI.txt;h=69dd29ed824e60c7290fab69f2df7848ddea7427;hb=de02d72bb3cc5b3d4c873db4ca8291723dd48479;hp=bc38283379f01d107ec710d96c0863109b68622e;hpb=0c326331c8b107abc0a160e8899d749150b8f76a;p=pandora-kernel.git diff --git a/Documentation/IPMI.txt b/Documentation/IPMI.txt index bc38283379f0..69dd29ed824e 100644 --- a/Documentation/IPMI.txt +++ b/Documentation/IPMI.txt @@ -365,6 +365,7 @@ You can change this at module load time (for a module) with: regshifts=,,... slave_addrs=,,... force_kipmid=,,... + kipmid_max_busy_us=,,... unload_when_empty=[0|1] Each of these except si_trydefaults is a list, the first item for the @@ -433,6 +434,7 @@ kernel command line as: ipmi_si.regshifts=,,... ipmi_si.slave_addrs=,,... ipmi_si.force_kipmid=,,... + ipmi_si.kipmid_max_busy_us=,,... It works the same as the module parameters of the same names. @@ -450,6 +452,16 @@ force this thread on or off. If you force it off and don't have interrupts, the driver will run VERY slowly. Don't blame me, these interfaces suck. +Unfortunately, this thread can use a lot of CPU depending on the +interface's performance. This can waste a lot of CPU and cause +various issues with detecting idle CPU and using extra power. To +avoid this, the kipmid_max_busy_us sets the maximum amount of time, in +microseconds, that kipmid will spin before sleeping for a tick. This +value sets a balance between performance and CPU waste and needs to be +tuned to your needs. Maybe, someday, auto-tuning will be added, but +that's not a simple thing and even the auto-tuning would need to be +tuned to the user's desired performance. + The driver supports a hot add and remove of interfaces. This way, interfaces can be added or removed after the kernel is up and running. This is done using /sys/modules/ipmi_si/parameters/hotmod, which is a