kernel 2.6.29.5 preempt

bgp starts normal and kernel know routes normaly like without patch
Here are some fib_triestats
cat /proc/net/fib_triestat

Basic info: size of leaf: 20 bytes, size of tnode: 36 bytes.

Main:

        Aver depth:     2.44

        Max depth:      6

        Leaves:         277888

        Prefixes:       291399

        Internal nodes: 66818

          1: 33080  2: 14584  3: 10788  4: 4911  5: 2185  6: 900  7:

366  8: 3  17: 1

        Pointers: 595584

Null ptrs: 250879

Total size: 18072  kB
Counters:

---------

gets = 1052940

backtracks = 55985

semantic match passed = 1034114

semantic match miss = 5

null node hit= 534415

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 = 1057636

backtracks = 1101307

semantic match passed = 4751

semantic match miss = 0

null node hit= 195605

skipped node resize = 0
kernel 2.6.29.5 no-preempt

All is ok like with preempt kernel (andl all working in normal time

"routes propagation")
cat /sys/module/fib_trie/parameters/sync_pages

1000
cat /proc/net/fib_triestat

Basic info: size of leaf: 20 bytes, size of tnode: 36 bytes.

Main:

        Aver depth:     2.45

        Max depth:      6

        Leaves:         277905

        Prefixes:       291416

        Internal nodes: 66863

          1: 33119  2: 14594  3: 10782  4: 4911  5: 2187  6: 901  7:

365  8: 3  17: 1

        Pointers: 595654

Null ptrs: 250887

Total size: 18074  kB
Counters:

---------

gets = 1060650

backtracks = 53161

semantic match passed = 1041008

semantic match miss = 12

null node hit= 504478

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 = 1065517

backtracks = 1095422

semantic match passed = 4954

semantic match miss = 0

null node hit= 195584

skipped node resize = 0
So i make tests with changing sync_pages

And
####################################

sync_pages: 64

total size reach maximum in 17sec
Basic info: size of leaf: 20 bytes, size of tnode: 36 bytes.

Main:

        Aver depth:     2.43

        Max depth:      6

        Leaves:         271928

        Prefixes:       285435

        Internal nodes: 66185

          1: 32904  2: 14554  3: 10740  4: 4677  5: 2047  6: 901  7:

361  17: 1

        Pointers: 585224

Null ptrs: 247112

Total size: 17729  kB
Counters:

---------

gets = 5313544

backtracks = 230501

semantic match passed = 5233998

semantic match miss = 61

null node hit= 2757531

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 = 5332471

backtracks = 4708505

semantic match passed = 19264

semantic match miss = 0

null node hit= 782757

skipped node resize = 0
######################################

sync_pages: 128

Fib trie Total size reach max in 14sec

Basic info: size of leaf: 20 bytes, size of tnode: 36 bytes.

Main:

        Aver depth:     2.44

        Max depth:      6

        Leaves:         277915

        Prefixes:       291427

        Internal nodes: 66832

          1: 33085  2: 14597  3: 10785  4: 4908  5: 2187  6: 900  7:

366  8: 3  17: 1

        Pointers: 595638

Null ptrs: 250892

Total size: 18074  kB
Counters:

---------

gets = 6698058

backtracks = 307491

semantic match passed = 6593421

semantic match miss = 66

null node hit= 3498560

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 = 6721120

backtracks = 5934017

semantic match passed = 23440

semantic match miss = 0

null node hit= 978008

skipped node resize = 0
#########################################

sync_pages: 256

hmm no difference also in 10sec
Basic info: size of leaf: 20 bytes, size of tnode: 36 bytes.

Main:

        Aver depth:     2.44

        Max depth:      6

        Leaves:         277913

        Prefixes:       291425

        Internal nodes: 66829

          1: 33082  2: 14596  3: 10786  4: 4909  5: 2186  6: 900  7:

366  8: 3  17: 1

        Pointers: 595620

Null ptrs: 250879

Total size: 18073  kB
Counters:

---------

gets = 4637474

backtracks = 188624

semantic match passed = 4577266

semantic match miss = 61

null node hit= 2451890

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 = 4651791

backtracks = 3716400

semantic match passed = 14613

semantic match miss = 0

null node hit= 587208

skipped node resize = 0
And with sync_pages higher that 256 time of filling kernel routes is the

same approx 10sec.
I make this test bu use:

watch -n1 cat /proc/net/fib_triestat

timer start when Total size was 1kB and stop when Total size reach 18073  kB
Regards

Paweł Staszewski
Jarek Poplawski pisze:

quoted text
> On Sun, Jul 05, 2009 at 02:32:32PM -0700, Paul E. McKenney wrote:

>

>> On Sun, Jul 05, 2009 at 07:32:08PM +0200, Jarek Poplawski wrote:

>>

>>> On Sun, Jul 05, 2009 at 06:20:03PM +0200, Jarek Poplawski wrote:

>>>

>>>> On Sun, Jul 05, 2009 at 02:30:03AM +0200, Paweł Staszewski wrote:

>>>>

>>>>> Oh

>>>>>

>>>>> I forgot - please Jarek give me patch with sync rcu and i will make test

>>>>> on preempt kernel

>>>>>

>>>> Probably non-preempt kernel might need something like this more, but

>>>> comparing is always interesting. This patch is based on Paul's

>>>> suggestion (I hope).

>>>>

>>> Hold on ;-) Here is something even better... Syncing after 128 pages

>>> might be still too slow, so here is a higher initial value, 1000, plus

>>> you can change this while testing in:

>>>

>>> /sys/module/fib_trie/parameters/sync_pages

>>>

>>> It would be interesting to find the lowest acceptable value.

>>>

>> Looks like a promising approach to me!

>>

>> 							Thanx, Paul

>>

>

> Hmm... As a matter of fact, I'm a bit sceptical now: I'm worrying this

> synchronize_rcu done at the lowest acceptable rate could be actually

> mostly idle or on the contrary too late. Probably some more complex

> (per cpu?) accounting would be necessary to really matter here, but

> on the other hand these problems weren't reported often enough.

>

> Thanks,

> Jarek P.

>

>

>>> ---> (synchronize take 8; apply on top of the 2.6.29.x with the last

>>>  	all-in-one patch, or net-2.6)

>>>

>>>  net/ipv4/fib_trie.c |   12 ++++++++++++

>>>  1 files changed, 12 insertions(+), 0 deletions(-)

>>>

>>> diff --git a/net/ipv4/fib_trie.c b/net/ipv4/fib_trie.c

>>> index 00a54b2..decc8d0 100644

>>> --- a/net/ipv4/fib_trie.c

>>> +++ b/net/ipv4/fib_trie.c

>>> @@ -71,6 +71,7 @@

>>>  #include

>>>  #include

>>>  #include

>>> +#include

>>>  #include

>>>  #include

>>>  #include

>>> @@ -164,6 +165,10 @@ 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 size_t tnode_free_size;

>>> +

>>> +static int sync_pages __read_mostly = 1000;

>>> +module_param(sync_pages, int, 0640);

>>>

>>>  static struct kmem_cache *fn_alias_kmem __read_mostly;

>>>  static struct kmem_cache *trie_leaf_kmem __read_mostly;

>>> @@ -393,6 +398,8 @@ static void tnode_free_safe(struct tnode *tn)

>>>  	BUG_ON(IS_LEAF(tn));

>>>  	tn->tnode_free = tnode_free_head;

>>>  	tnode_free_head = tn;

>>> +	tnode_free_size += sizeof(struct tnode) +

>>> +			   (sizeof(struct node *) << tn->bits);

>>>  }

>>>

>>>  static void tnode_free_flush(void)

>>> @@ -404,6 +411,11 @@ static void tnode_free_flush(void)

>>>  		tn->tnode_free = NULL;

>>>  		tnode_free(tn);

>>>  	}

>>> +

>>> +	if (tnode_free_size >= PAGE_SIZE * sync_pages) {

>>> +		tnode_free_size = 0;

>>> +		synchronize_rcu();

>>> +	}

>>>  }

>>>

>>>  static struct leaf *leaf_new(void)

>>> --

>>> 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

>>>

>

>

>   

--

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