The driver only behaves this way on systems where it has to. If the BMC System Interface (SI) provides an interrupt, the kernel thread doesn't run. Everything is interrupt driven.
Anyone doing system software for x86 servers should be harrassing the hardware vendors to get this right... Interrupts can be used with any of the SIs (BT, KCS, SMIC), but BT has the dual advantages of doing its transfers all at once via DMA, and having a well defined interrupt mechanism. Hardware designers implementing an interrupt for KCS or SMIC have to guess at a few too many details. Agitate for BT IPMI SI! (HP's IPMI causes the least drag of any of the big vendors. Although they use the same crummy char-by-char KCS SI [SMIC on older systems], they always provide an IPMI interrupt. I've heard that some modern Sun models use BT; haven't seen it in action yet.) >Bela< > -----Original Message----- > From: Ferenc Wagner [mailto:[email protected]] > Sent: Thursday, May 21, 2009 2:47 AM > To: Corey Minyard > Cc: Andrew Morton; [email protected]; > [email protected] > Subject: Re: [Openipmi-developer] modprobe ipmi_si hangs > under 2.6.30-rc5 > > Corey Minyard <[email protected]> writes: > > > Ferenc Wagner wrote: > > > >> Just out of interest, how often does the driver wake up to check > >> the inteface? > > > > When idle, the driver wakes up every 10ms to check for something on > > the driver. > > Wow, 100 times per second, that sure sounds gross for piping out SEL > entries! Though it certainly doesn't matter much for our servers, but > hasn't it got the potential to heavily tax laptop batteries? Or is > that why ipmi_si isn't loaded automatically by udev? > -- > Thanks, > Feri. > > -------------------------------------------------------------- > ---------------- > Register Now for Creativity and Technology (CaT), June 3rd, NYC. CaT > is a gathering of tech-side developers & brand creativity > professionals. Meet > the minds behind Google Creative Lab, Visual Complexity, > Processing, & > iPhoneDevCamp asthey present alongside digital heavyweights > like Barbarian > Group, R/GA, & Big Spaceship. http://www.creativitycat.com > _______________________________________________ > Openipmi-developer mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/openipmi-developer > ------------------------------------------------------------------------------ Register Now for Creativity and Technology (CaT), June 3rd, NYC. CaT is a gathering of tech-side developers & brand creativity professionals. Meet the minds behind Google Creative Lab, Visual Complexity, Processing, & iPhoneDevCamp as they present alongside digital heavyweights like Barbarian Group, R/GA, & Big Spaceship. http://p.sf.net/sfu/creativitycat-com _______________________________________________ Openipmi-developer mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/openipmi-developer
