Messages in this thread | | | Subject | Re: Better pagecache statistics ? | From | Badari Pulavarty <> | Date | Thu, 01 Dec 2005 10:24:17 -0800 |
| |
On Thu, 2005-12-01 at 15:57 -0200, Marcelo Tosatti wrote: > On Thu, Dec 01, 2005 at 06:21:39PM +0100, Arjan van de Ven wrote: > > On Thu, 2005-12-01 at 09:15 -0800, Badari Pulavarty wrote: > > > > Most of the issues you mention are null if you move the stats > > > > maintenance burden to userspace. > > > > > > > > The performance impact is also minimized since the hooks > > > > (read: overhead) can be loaded on-demand as needed. > > > > > > > > > > The overhead is - going through each mapping/inode in the system > > > and dumping out "nrpages" - to get per-file statistics. This is > > > going to be expensive, need locking and there is no single list > > > we can traverse to get it. I am not sure how to do this. > > Can't you add hooks to add_to_page_cache/remove_from_page_cache > to record pagecache activity ?
BTW, the hook can't be dynamically loaded (using kprobes) - since we miss what happend till then.
Thanks, Badari
- 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/
| |