diff mbox series

[v3] ipvs: increase ip_vs_conn_tab_bits range for 64BIT

Message ID 20230412-increase_ipvs_conn_tab_bits-v3-1-c813278f2d24@gmail.com
State Accepted
Delegated to: Pablo Neira
Headers show
Series [v3] ipvs: increase ip_vs_conn_tab_bits range for 64BIT | expand

Commit Message

Abhijeet Rastogi May 17, 2023, 3:08 a.m. UTC
Current range [8, 20] is set purely due to historical reasons
because at the time, ~1M (2^20) was considered sufficient.
With this change, 27 is the upper limit for 64-bit, 20 otherwise.

Previous change regarding this limit is here.

Link: https://lore.kernel.org/all/86eabeb9dd62aebf1e2533926fdd13fed48bab1f.1631289960.git.aclaudi@redhat.com/T/#u

Signed-off-by: Abhijeet Rastogi <abhijeet.1989@gmail.com>
---
The conversation for this started at: 

https://www.spinics.net/lists/netfilter/msg60995.html

The upper limit for algo is any bit size less than 32, so this
change will allow us to set bit size > 20. Today, it is common to have
RAM available to handle greater than 2^20 connections per-host.

Distros like RHEL already allow setting limits higher than 20.
---
Changes in v3:
- Fix text width in Kconfig, now text is 70 columns, excluding tab.
- Link to v2: https://lore.kernel.org/r/20230412-increase_ipvs_conn_tab_bits-v2-1-994c0df018e6@gmail.com

Changes in v2:
- Lower the ranges, 27 for 64bit, 20 otherwise
- Link to v1: https://lore.kernel.org/r/20230412-increase_ipvs_conn_tab_bits-v1-1-60a4f9f4c8f2@gmail.com
---
 net/netfilter/ipvs/Kconfig      | 27 ++++++++++++++-------------
 net/netfilter/ipvs/ip_vs_conn.c |  4 ++--
 2 files changed, 16 insertions(+), 15 deletions(-)


---
base-commit: 09a9639e56c01c7a00d6c0ca63f4c7c41abe075d
change-id: 20230412-increase_ipvs_conn_tab_bits-4322c90da216

Best regards,

Comments

Julian Anastasov May 17, 2023, 12:29 p.m. UTC | #1
Hello,

On Tue, 16 May 2023, Abhijeet Rastogi wrote:

> Current range [8, 20] is set purely due to historical reasons
> because at the time, ~1M (2^20) was considered sufficient.
> With this change, 27 is the upper limit for 64-bit, 20 otherwise.
> 
> Previous change regarding this limit is here.
> 
> Link: https://lore.kernel.org/all/86eabeb9dd62aebf1e2533926fdd13fed48bab1f.1631289960.git.aclaudi@redhat.com/T/#u
> 
> Signed-off-by: Abhijeet Rastogi <abhijeet.1989@gmail.com>

	Looks good to me, thanks!

Acked-by: Julian Anastasov <ja@ssi.bg>

	I'll post my patch on top of this.

> ---
> The conversation for this started at: 
> 
> https://www.spinics.net/lists/netfilter/msg60995.html
> 
> The upper limit for algo is any bit size less than 32, so this
> change will allow us to set bit size > 20. Today, it is common to have
> RAM available to handle greater than 2^20 connections per-host.
> 
> Distros like RHEL already allow setting limits higher than 20.
> ---
> Changes in v3:
> - Fix text width in Kconfig, now text is 70 columns, excluding tab.
> - Link to v2: https://lore.kernel.org/r/20230412-increase_ipvs_conn_tab_bits-v2-1-994c0df018e6@gmail.com
> 
> Changes in v2:
> - Lower the ranges, 27 for 64bit, 20 otherwise
> - Link to v1: https://lore.kernel.org/r/20230412-increase_ipvs_conn_tab_bits-v1-1-60a4f9f4c8f2@gmail.com
> ---
>  net/netfilter/ipvs/Kconfig      | 27 ++++++++++++++-------------
>  net/netfilter/ipvs/ip_vs_conn.c |  4 ++--
>  2 files changed, 16 insertions(+), 15 deletions(-)
> 
> diff --git a/net/netfilter/ipvs/Kconfig b/net/netfilter/ipvs/Kconfig
> index 271da8447b29..2a3017b9c001 100644
> --- a/net/netfilter/ipvs/Kconfig
> +++ b/net/netfilter/ipvs/Kconfig
> @@ -44,7 +44,8 @@ config	IP_VS_DEBUG
>  
>  config	IP_VS_TAB_BITS
>  	int "IPVS connection table size (the Nth power of 2)"
> -	range 8 20
> +	range 8 20 if !64BIT
> +	range 8 27 if 64BIT
>  	default 12
>  	help
>  	  The IPVS connection hash table uses the chaining scheme to handle
> @@ -54,24 +55,24 @@ config	IP_VS_TAB_BITS
>  
>  	  Note the table size must be power of 2. The table size will be the
>  	  value of 2 to the your input number power. The number to choose is
> -	  from 8 to 20, the default number is 12, which means the table size
> -	  is 4096. Don't input the number too small, otherwise you will lose
> -	  performance on it. You can adapt the table size yourself, according
> -	  to your virtual server application. It is good to set the table size
> -	  not far less than the number of connections per second multiplying
> -	  average lasting time of connection in the table.  For example, your
> -	  virtual server gets 200 connections per second, the connection lasts
> -	  for 200 seconds in average in the connection table, the table size
> -	  should be not far less than 200x200, it is good to set the table
> -	  size 32768 (2**15).
> +	  from 8 to 27 for 64BIT(20 otherwise), the default number is 12,
> +	  which means the table size is 4096. Don't input the number too
> +	  small, otherwise you will lose performance on it. You can adapt the
> +	  table size yourself, according to your virtual server application.
> +	  It is good to set the table size not far less than the number of
> +	  connections per second multiplying average lasting time of
> +	  connection in the table.  For example, your virtual server gets 200
> +	  connections per second, the connection lasts for 200 seconds in
> +	  average in the connection table, the table size should be not far
> +	  less than 200x200, it is good to set the table size 32768 (2**15).
>  
>  	  Another note that each connection occupies 128 bytes effectively and
>  	  each hash entry uses 8 bytes, so you can estimate how much memory is
>  	  needed for your box.
>  
>  	  You can overwrite this number setting conn_tab_bits module parameter
> -	  or by appending ip_vs.conn_tab_bits=? to the kernel command line
> -	  if IP VS was compiled built-in.
> +	  or by appending ip_vs.conn_tab_bits=? to the kernel command line if
> +	  IP VS was compiled built-in.
>  
>  comment "IPVS transport protocol load balancing support"
>  
> diff --git a/net/netfilter/ipvs/ip_vs_conn.c b/net/netfilter/ipvs/ip_vs_conn.c
> index 13534e02346c..e1b9b52909a5 100644
> --- a/net/netfilter/ipvs/ip_vs_conn.c
> +++ b/net/netfilter/ipvs/ip_vs_conn.c
> @@ -1484,8 +1484,8 @@ int __init ip_vs_conn_init(void)
>  	int idx;
>  
>  	/* Compute size and mask */
> -	if (ip_vs_conn_tab_bits < 8 || ip_vs_conn_tab_bits > 20) {
> -		pr_info("conn_tab_bits not in [8, 20]. Using default value\n");
> +	if (ip_vs_conn_tab_bits < 8 || ip_vs_conn_tab_bits > 27) {
> +		pr_info("conn_tab_bits not in [8, 27]. Using default value\n");
>  		ip_vs_conn_tab_bits = CONFIG_IP_VS_TAB_BITS;
>  	}
>  	ip_vs_conn_tab_size = 1 << ip_vs_conn_tab_bits;
> 
> ---
> base-commit: 09a9639e56c01c7a00d6c0ca63f4c7c41abe075d
> change-id: 20230412-increase_ipvs_conn_tab_bits-4322c90da216
> 
> Best regards,
> -- 
> Abhijeet Rastogi <abhijeet.1989@gmail.com>

Regards

--
Julian Anastasov <ja@ssi.bg>
Simon Horman May 18, 2023, 6:52 p.m. UTC | #2
On Tue, May 16, 2023 at 08:08:49PM -0700, Abhijeet Rastogi wrote:
> Current range [8, 20] is set purely due to historical reasons
> because at the time, ~1M (2^20) was considered sufficient.
> With this change, 27 is the upper limit for 64-bit, 20 otherwise.
> 
> Previous change regarding this limit is here.
> 
> Link: https://lore.kernel.org/all/86eabeb9dd62aebf1e2533926fdd13fed48bab1f.1631289960.git.aclaudi@redhat.com/T/#u
> 
> Signed-off-by: Abhijeet Rastogi <abhijeet.1989@gmail.com>

Acked-by: Simon Horman <horms@kernel.org>
Pablo Neira Ayuso June 1, 2023, 7:17 p.m. UTC | #3
On Tue, May 16, 2023 at 08:08:49PM -0700, Abhijeet Rastogi wrote:
> Current range [8, 20] is set purely due to historical reasons
> because at the time, ~1M (2^20) was considered sufficient.
> With this change, 27 is the upper limit for 64-bit, 20 otherwise.
> 
> Previous change regarding this limit is here.
>
> Link: https://lore.kernel.org/all/86eabeb9dd62aebf1e2533926fdd13fed48bab1f.1631289960.git.aclaudi@redhat.com/T/#u

Applied to nf-next, thanks
Simon Horman June 29, 2023, 6:02 a.m. UTC | #4
On Wed, Jun 28, 2023 at 02:54:59PM -0700, Abhijeet Rastogi wrote:
> Hi Pablo,
> 
> Thanks for applying to nf-next.
> 
> Sorry for a noob question, I see that the commit is here now:
> https://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf-next.git/commit/?id=04292c695f82b6cf0d25dd5ae494f16ddbb621f6
> 
> How long before it's merged on github.com/torvalds/linux/?

Hi Abhijeet,

Please don't top-post on Kernel mailing lists.

I believe that your patch propagated into Linux's tree
(github.com/torvalds/linux/) within the last 24h.
And should be included in v6.5-rc1 and from there v6.5.

I would expect v6.5-rc1 to be released in approximately 10 days.
And v6.5 to be released in approximately 9 weeks.

> On Thu, Jun 1, 2023 at 12:17 PM Pablo Neira Ayuso <pablo@netfilter.org>
> wrote:
> 
> > On Tue, May 16, 2023 at 08:08:49PM -0700, Abhijeet Rastogi wrote:
> > > Current range [8, 20] is set purely due to historical reasons
> > > because at the time, ~1M (2^20) was considered sufficient.
> > > With this change, 27 is the upper limit for 64-bit, 20 otherwise.
> > >
> > > Previous change regarding this limit is here.
> > >
> > > Link:
> > https://lore.kernel.org/all/86eabeb9dd62aebf1e2533926fdd13fed48bab1f.1631289960.git.aclaudi@redhat.com/T/#u
> >
> > Applied to nf-next, thanks
> >
> 
> 
> -- 
> Cheers,
> Abhijeet (https://abhi.host)
diff mbox series

Patch

diff --git a/net/netfilter/ipvs/Kconfig b/net/netfilter/ipvs/Kconfig
index 271da8447b29..2a3017b9c001 100644
--- a/net/netfilter/ipvs/Kconfig
+++ b/net/netfilter/ipvs/Kconfig
@@ -44,7 +44,8 @@  config	IP_VS_DEBUG
 
 config	IP_VS_TAB_BITS
 	int "IPVS connection table size (the Nth power of 2)"
-	range 8 20
+	range 8 20 if !64BIT
+	range 8 27 if 64BIT
 	default 12
 	help
 	  The IPVS connection hash table uses the chaining scheme to handle
@@ -54,24 +55,24 @@  config	IP_VS_TAB_BITS
 
 	  Note the table size must be power of 2. The table size will be the
 	  value of 2 to the your input number power. The number to choose is
-	  from 8 to 20, the default number is 12, which means the table size
-	  is 4096. Don't input the number too small, otherwise you will lose
-	  performance on it. You can adapt the table size yourself, according
-	  to your virtual server application. It is good to set the table size
-	  not far less than the number of connections per second multiplying
-	  average lasting time of connection in the table.  For example, your
-	  virtual server gets 200 connections per second, the connection lasts
-	  for 200 seconds in average in the connection table, the table size
-	  should be not far less than 200x200, it is good to set the table
-	  size 32768 (2**15).
+	  from 8 to 27 for 64BIT(20 otherwise), the default number is 12,
+	  which means the table size is 4096. Don't input the number too
+	  small, otherwise you will lose performance on it. You can adapt the
+	  table size yourself, according to your virtual server application.
+	  It is good to set the table size not far less than the number of
+	  connections per second multiplying average lasting time of
+	  connection in the table.  For example, your virtual server gets 200
+	  connections per second, the connection lasts for 200 seconds in
+	  average in the connection table, the table size should be not far
+	  less than 200x200, it is good to set the table size 32768 (2**15).
 
 	  Another note that each connection occupies 128 bytes effectively and
 	  each hash entry uses 8 bytes, so you can estimate how much memory is
 	  needed for your box.
 
 	  You can overwrite this number setting conn_tab_bits module parameter
-	  or by appending ip_vs.conn_tab_bits=? to the kernel command line
-	  if IP VS was compiled built-in.
+	  or by appending ip_vs.conn_tab_bits=? to the kernel command line if
+	  IP VS was compiled built-in.
 
 comment "IPVS transport protocol load balancing support"
 
diff --git a/net/netfilter/ipvs/ip_vs_conn.c b/net/netfilter/ipvs/ip_vs_conn.c
index 13534e02346c..e1b9b52909a5 100644
--- a/net/netfilter/ipvs/ip_vs_conn.c
+++ b/net/netfilter/ipvs/ip_vs_conn.c
@@ -1484,8 +1484,8 @@  int __init ip_vs_conn_init(void)
 	int idx;
 
 	/* Compute size and mask */
-	if (ip_vs_conn_tab_bits < 8 || ip_vs_conn_tab_bits > 20) {
-		pr_info("conn_tab_bits not in [8, 20]. Using default value\n");
+	if (ip_vs_conn_tab_bits < 8 || ip_vs_conn_tab_bits > 27) {
+		pr_info("conn_tab_bits not in [8, 27]. Using default value\n");
 		ip_vs_conn_tab_bits = CONFIG_IP_VS_TAB_BITS;
 	}
 	ip_vs_conn_tab_size = 1 << ip_vs_conn_tab_bits;