On Thu, Apr 25, 2013 at 11:05:26AM +0200, Hans Schillstrom wrote: > Hello > On Thu, 2013-04-25 at 11:15 +0300, Julian Anastasov wrote: > > Hello, > > > > On Thu, 25 Apr 2013, Simon Horman wrote: > > > > > It is unclear to me that there is any utility in the following: > > > > > > rcu_read_unlock(); > > > rcu_read_lock(); > > > > I thought it is a good idea for fixed hash table > > of IP_VS_TAB_BITS=20. May be if guarded by > > > > if (!((++idx) & 4095)) > > > > to reduce its rate to 256 (with idx++ removed from the for loop) ? > > > > Netfilter has no such logic for nf_conntrack because > > it has limit of 16384 rows. Not sure how fatal is to try 1048576 > > empty rows under RCU lock for such rare operations as > > connection listing. OTOH, ip_vs_conn_array() needs to > > seek at some initial position, so it can skip many > > entries if reading table with many conns, for example, > > 1048576 rows * 16 conns per row, we will need to > > touch 16777216 conns under lock. Not sure what is the > > best practice for such cases. > > My opinion is to keep it, people tends to do such "rare" things. > It's not unusual with 256k - 1M rows... Ok, leaving it seems reasonable. Pablo, do you have any objections? -- To unsubscribe from this list: send the line "unsubscribe netfilter-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
