On 2015-03-11 09:48 PM, Valdis.Kletnieks@xxxxxx wrote: > On Wed, 11 Mar 2015 19:03:33 -0400, Nicholas Krause said: > >> was wondering of how this would improve file system scalability and >> reliability if implemented in file system code for btrfs worker threads. > > Step 1: Figure out what locks are contended in actual systems. > Step 2: Determine if the scope of a contended lock can be reduced. > Step 3: ??? > Step 4: Profit! > > Note that improving scalability will often cause reliability issues, > because as you decompose locks into sets of smaller locks, you increase > the number of ways you can get it wrong. The BKL, for all its uglyness, > was pretty hard to screw up. On the other hand, we probably would never > have gotten rid of it if somebody hadn't put lockdep into the kernel. It > was painful enough even with automated testing tools.... > Thanks Valdis, That makes sense to me. I was wondering however about the reader vs writer issues in file systems too as this seems to me coming up a lot in btrfs and other file systems for various reasons. Thanks Nick _______________________________________________ Kernelnewbies mailing list Kernelnewbies@xxxxxxxxxxxxxxxxx http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
