Re: rib_trie / Fix inflate_threshold_root. Now=15 size=11 bits
From: Paweł Staszewski <hidden>
Date: 2009-06-29 08:47:45
But With all this patches i have the same problem with CPU load Every time when route cache entries are purged cpu load is increasing from 1% to 40 / 80% it depends I see that on 64bit machine when route cache entries are going down i have almost 80% load on each cpu where ethernet card is binded by smp_affinity But on 32bit machine cpu load reported by mpstat is half that on 64bit machine here is example from 32bit machine ( mpstat + rtstat -k entries ) Linux 2.6.29.5 (TM_02_C1) 06/29/09 _i686_ (2 CPU) 12:36:54 CPU %usr %nice %sys %iowait %irq %soft %steal %guest %idle RT CACHE ENTRIES (from rtstat) 12:36:57 all 0.00 0.00 0.00 0.00 1.51 15.08 0.00 0.00 83.42 83346 12:36:58 all 0.00 0.00 0.00 0.00 1.01 7.58 0.00 0.00 91.41 85988 12:36:59 all 0.00 0.00 0.00 0.00 0.50 1.01 0.00 0.00 98.49 89979 12:37:00 all 0.00 0.00 0.50 0.00 0.00 1.51 0.00 0.00 97.99 93652 12:37:01 all 0.00 0.00 0.00 0.00 0.00 2.01 0.00 0.00 97.99 96533 12:37:02 all 0.00 0.00 0.00 0.00 0.51 1.01 0.00 0.00 98.48 99451 12:37:03 all 0.00 0.00 0.00 0.00 0.00 2.49 0.00 0.00 97.51 102018 12:37:04 all 0.00 0.00 0.00 0.00 0.00 1.52 0.00 0.00 98.48 104153 12:37:05 all 0.00 0.00 0.00 0.00 0.00 1.01 0.00 0.00 98.99 105979 12:37:06 all 0.00 0.00 0.00 0.00 0.00 1.01 0.00 0.00 98.99 107684 12:37:07 all 0.00 0.00 0.00 0.00 0.00 1.53 0.00 0.00 98.47 109070 12:37:08 all 0.00 0.00 0.00 0.00 0.00 1.51 0.00 0.00 98.49 110462 12:37:09 all 0.00 0.00 0.00 0.00 0.00 1.52 0.00 0.00 98.48 112301 12:37:10 all 0.00 0.00 0.00 0.00 2.00 20.00 0.00 0.00 78.00 111535 12:37:11 all 0.00 0.00 0.00 0.00 2.49 34.33 0.00 0.00 63.18 108659 12:37:12 all 0.00 0.00 0.00 0.00 3.03 28.28 0.00 0.00 68.69 105534 12:37:13 all 0.00 0.00 0.00 0.00 3.98 30.85 0.00 0.00 65.17 103341 12:37:14 all 0.00 0.00 0.00 0.00 4.50 30.50 0.00 0.00 65.00 101307 12:37:15 all 5.56 0.00 0.00 0.00 1.52 28.79 0.00 0.00 64.14 97435 12:37:16 all 11.39 0.00 0.50 0.00 4.95 30.69 0.00 0.00 52.48 93908 12:37:17 all 1.51 0.00 0.00 0.00 1.01 27.64 0.00 0.00 69.85 90229 12:37:18 all 0.00 0.00 0.00 0.00 2.99 27.36 0.00 0.00 69.65 87030 12:37:19 all 0.00 0.00 0.00 0.00 3.02 29.65 0.00 0.00 67.34 84324 12:37:20 all 0.00 0.00 0.00 0.00 2.99 30.35 0.00 0.00 66.67 82167 12:37:21 all 0.00 0.00 0.00 0.00 1.98 31.68 0.00 0.00 66.34 80121 12:37:22 all 0.00 0.00 0.00 0.00 1.51 30.65 0.00 0.00 67.84 77850 12:37:23 all 0.00 0.00 0.00 0.00 2.50 28.50 0.00 0.00 69.00 76005 12:37:24 all 0.00 0.00 0.00 0.00 1.98 23.27 0.00 0.00 74.75 74538 12:37:25 all 0.00 0.00 0.49 0.00 2.93 22.44 0.00 0.00 74.15 76923 12:37:26 all 0.00 0.00 0.00 0.00 1.51 15.58 0.00 0.00 82.91 79396 12:37:27 all 0.00 0.00 0.00 0.00 0.50 7.96 0.00 0.00 91.54 81835 12:37:28 all 0.00 0.00 0.00 0.00 0.50 3.52 0.00 0.00 95.98 84169 12:37:29 all 0.00 0.00 0.00 0.00 0.00 2.02 0.00 0.00 97.98 87740 12:37:30 all 0.00 0.00 0.00 0.00 0.51 1.52 0.00 0.00 97.98 91152 12:37:31 all 0.00 0.00 0.00 0.00 0.00 1.99 0.00 0.00 98.01 94102 12:37:32 all 0.00 0.00 0.00 0.00 0.00 1.52 0.00 0.00 98.48 97032 12:37:33 all 0.00 0.00 0.00 0.00 0.00 0.50 0.00 0.00 99.50 99685 12:37:34 all 0.00 0.00 0.00 0.00 0.00 1.00 0.00 0.00 99.00 101970 12:37:35 all 0.00 0.00 0.00 0.00 0.50 1.00 0.00 0.00 98.50 103814 12:37:36 all 0.00 0.00 0.00 0.00 0.00 1.52 0.00 0.00 98.48 104793 12:37:37 all 0.00 0.00 0.00 0.00 0.00 1.01 0.00 0.00 98.99 106214 12:37:38 all 0.00 0.00 0.00 0.00 0.50 1.01 0.00 0.00 98.49 107300 12:37:39 all 0.00 0.00 0.00 0.00 0.00 13.00 0.00 0.00 87.00 111951 12:37:40 all 0.00 0.00 0.00 0.00 2.50 29.50 0.00 0.00 68.00 111215 12:37:41 all 0.00 0.00 0.00 0.00 2.01 30.65 0.00 0.00 67.34 108023 12:37:42 all 0.00 0.00 0.00 0.00 2.99 29.85 0.00 0.00 67.16 104751 12:37:43 all 0.00 0.00 0.00 0.00 2.00 31.00 0.00 0.00 67.00 100827 12:37:44 all 0.00 0.00 0.00 0.00 3.00 27.00 0.00 0.00 70.00 97184 12:37:45 all 0.00 0.00 0.00 0.00 2.50 29.00 0.00 0.00 68.50 93904 12:37:46 all 0.00 0.00 0.00 0.00 3.02 30.15 0.00 0.00 66.83 90979 12:37:47 all 0.00 0.00 0.00 0.00 2.49 27.86 0.00 0.00 69.65 88315 12:37:48 all 0.00 0.00 0.00 0.00 2.48 31.19 0.00 0.00 66.34 87777 12:37:49 all 0.00 0.00 0.00 0.00 2.94 32.35 0.00 0.00 64.71 89218 12:37:50 all 0.00 0.00 0.00 0.00 3.00 32.50 0.00 0.00 64.50 85896 12:37:51 all 0.00 0.00 0.00 0.00 2.50 30.00 0.00 0.00 67.50 82712 12:37:52 all 0.50 0.00 0.00 0.00 2.49 30.85 0.00 0.00 66.17 79137 12:37:53 all 0.00 0.00 0.50 0.00 2.00 28.50 0.00 0.00 69.00 75644 12:37:54 all 0.00 0.00 0.00 0.00 2.51 30.65 0.00 0.00 66.83 72843 12:37:55 all 0.00 0.00 0.50 0.00 3.48 28.36 0.00 0.00 67.66 73460 Paweł Staszewski pisze:
Jarek Poplawski pisze:quoted
To David Miller: since among patches tested negatively by Pawel are current 2 fixes from 2.6.31-rc, I hope they weren't sent to -stable yet. Otherwise, please withdraw them until they are tested alone. Thanks. To Pawel: On Sun, Jun 28, 2009 at 05:48:19PM +0200, Paweł Staszewski wrote:quoted
After apply this patch something is wrong Traffic is not forwarded no info in dmesg / no info from bgp and also i can't connect to bgpd process I revert kernel to past version with first Jarek patchSince checking this can take time I attach here a patch with only changes which are currently in 2.6.31-rc. Of course, this part can be broken as well, so it's up to you: if you could try it with caution somewhere it would be very helpful; otherwise don't bother. It could be applied to 2.6.29 with or without this currently working patch.Ok. I applied this patch 15mins ago to 2.6.29.5 and now it's working - traffic is forwarded. Some fib_triestats cat /proc/net/fib_triestat Basic info: size of leaf: 20 bytes, size of tnode: 36 bytes. Main: Aver depth: 2.29 Max depth: 6 Leaves: 277015 Prefixes: 290493 Internal nodes: 67115 1: 35733 2: 13635 3: 9544 4: 4832 5: 2239 6: 1125 7: 5 9: 1 18: 1 Pointers: 686614 Null ptrs: 342485 Total size: 18396 kB Counters: --------- gets = 3956301 backtracks = 192497 semantic match passed = 3895955 semantic match miss = 133 null node hit= 4306948 skipped node resize = 0 Local: Aver depth: 3.75 Max depth: 5 Leaves: 12 Prefixes: 13 Internal nodes: 10 1: 9 2: 1 Pointers: 22 Null ptrs: 1 Total size: 2 kB Counters: --------- gets = 3960981 backtracks = 2152441 semantic match passed = 4757 semantic match miss = 0 null node hit= 194997 skipped node resize = 0quoted
Thanks, Jarek P.--- (for 2.6.29.x, .28 or .27)diff -Nurp a/net/ipv4/fib_trie.c b/net/ipv4/fib_trie.c--- a/net/ipv4/fib_trie.c 2009-06-27 20:25:06.000000000 +0200 +++ b/net/ipv4/fib_trie.c 2009-06-28 23:06:02.000000000 +0200@@ -123,6 +123,7 @@ struct tnode { union { struct rcu_head rcu; struct work_struct work; + struct tnode *tnode_free; }; struct node *child[0]; };@@ -161,6 +162,8 @@ static void tnode_put_child_reorg(struct static struct node *resize(struct trie *t, struct tnode *tn); static struct tnode *inflate(struct trie *t, struct tnode *tn); static struct tnode *halve(struct trie *t, struct tnode *tn); +/* tnodes to free after resize(); protected by RTNL */ +static struct tnode *tnode_free_head; static struct kmem_cache *fn_alias_kmem __read_mostly; static struct kmem_cache *trie_leaf_kmem __read_mostly;@@ -385,6 +388,24 @@ static inline void tnode_free(struct tno call_rcu(&tn->rcu, __tnode_free_rcu); } +static void tnode_free_safe(struct tnode *tn) +{ + BUG_ON(IS_LEAF(tn)); + tn->tnode_free = tnode_free_head; + tnode_free_head = tn; +} + +static void tnode_free_flush(void) +{ + struct tnode *tn; + + while ((tn = tnode_free_head)) { + tnode_free_head = tn->tnode_free; + tn->tnode_free = NULL; + tnode_free(tn); + } +} + static struct leaf *leaf_new(void) { struct leaf *l = kmem_cache_alloc(trie_leaf_kmem, GFP_KERNEL);@@ -495,7 +516,7 @@ static struct node *resize(struct trie * /* No children */ if (tn->empty_children == tnode_child_length(tn)) { - tnode_free(tn); + tnode_free_safe(tn); return NULL; } /* One child */@@ -509,7 +530,7 @@ static struct node *resize(struct trie * /* compress one level */ node_set_parent(n, NULL); - tnode_free(tn); + tnode_free_safe(tn); return n; } /*@@ -670,7 +691,7 @@ static struct node *resize(struct trie * /* compress one level */ node_set_parent(n, NULL); - tnode_free(tn); + tnode_free_safe(tn); return n; }@@ -756,7 +777,7 @@ static struct tnode *inflate(struct trie put_child(t, tn, 2*i, inode->child[0]); put_child(t, tn, 2*i+1, inode->child[1]); - tnode_free(inode); + tnode_free_safe(inode); continue; }@@ -801,9 +822,9 @@ static struct tnode *inflate(struct trie put_child(t, tn, 2*i, resize(t, left)); put_child(t, tn, 2*i+1, resize(t, right)); - tnode_free(inode); + tnode_free_safe(inode); } - tnode_free(oldtnode); + tnode_free_safe(oldtnode); return tn; nomem: {@@ -885,7 +906,7 @@ static struct tnode *halve(struct trie * put_child(t, newBinNode, 1, right); put_child(t, tn, i/2, resize(t, newBinNode)); } - tnode_free(oldtnode); + tnode_free_safe(oldtnode); return tn; nomem: {@@ -983,12 +1004,14 @@ fib_find_node(struct trie *t, u32 key) return NULL; } -static struct node *trie_rebalance(struct trie *t, struct tnode *tn) +static void trie_rebalance(struct trie *t, struct tnode *tn) { int wasfull; - t_key cindex, key = tn->key; + t_key cindex, key; struct tnode *tp; + key = tn->key; + while (tn != NULL && (tp = node_parent((struct node *)tn)) !=NULL) { cindex = tkey_extract_bits(key, tp->pos, tp->bits); wasfull = tnode_full(tp, tnode_get_child(tp, cindex));@@ -998,6 +1021,7 @@ static struct node *trie_rebalance(struc (struct node *)tn, wasfull); tp = node_parent((struct node *) tn); + tnode_free_flush(); if (!tp) break; tn = tp;@@ -1007,7 +1031,10 @@ static struct node *trie_rebalance(struc if (IS_TNODE(tn)) tn = (struct tnode *)resize(t, (struct tnode *)tn); - return (struct node *)tn; + rcu_assign_pointer(t->trie, (struct node *)tn); + tnode_free_flush(); + + return; } /* only used from updater-side */@@ -1155,7 +1182,7 @@ static struct list_head *fib_insert_node /* Rebalance the trie */ - rcu_assign_pointer(t->trie, trie_rebalance(t, tp)); + trie_rebalance(t, tp); done: return fa_head; }@@ -1575,7 +1602,7 @@ static void trie_leaf_remove(struct trie if (tp) { t_key cindex = tkey_extract_bits(l->key, tp->pos, tp->bits); put_child(t, (struct tnode *)tp, cindex, NULL); - rcu_assign_pointer(t->trie, trie_rebalance(t, tp)); + trie_rebalance(t, tp); } else rcu_assign_pointer(t->trie, NULL);-- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html