On Wed, Aug 03, 2011 at 02:21:25PM -0400, Robert Haas wrote: > It would be nice if the Linux guys would fix this problem for us, but > I'm not sure whether they will. For those who may be curious, the > problem is in generic_file_llseek() in fs/read-write.c. On a platform > with 8-byte atomic reads, it seems like it ought to be very possible > to read inode->i_size without taking a spinlock.
Interesting. There's this thread from 2003 suggesting the use of pread instead, it was rejected on the argument that lseek is cheap so not a problem. http://archives.postgresql.org/pgsql-patches/2003-02/msg00197.php Perhaps we now have a benchmark where the effect can be measured. There's the issue about whether it screws up the readahead mechanism... Have a nice day, -- Martijn van Oosterhout <klep...@svana.org> http://svana.org/kleptog/ > He who writes carelessly confesses thereby at the very outset that he does > not attach much importance to his own thoughts. -- Arthur Schopenhauer
signature.asc
Description: Digital signature
