Messages in this thread |  | | Date | Fri, 28 Dec 2001 09:33:48 -0800 (PST) | From | Davide Libenzi <> | Subject | Re: 2.4.17 absurd number of context switches |
| |
On Fri, 28 Dec 2001, Alan Cox wrote:
> > > The scheduler is _good_ at the three process case. Run some straces it looks > > > more like postgres is doing wacky yield based locks. > > > > The scheduler that Linus merged in 2.5.2-pre3 will solve the problem. > > Looking at the postgres traces here it wont make any difference at all. Not > one iota. If I am reading it right I have processes each going > yield, yield, yield... so the kernel does just that (and indeed posix > semantics require that behaviour).
task A old the lock , counter = 2 task B counter = 5 and task C counter = 4 are woke up try to look at a switch dump. the scheduler will spend 3 entire time slices switching between B and C before A will get back the CPU and will free the lock.
- Davide
- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
|  |