Re: how to change the default size of hash table?

[Ratz <ratz@xxxxxx>]

Hi

He Weitao wrote:
> 
> Hi, all
> 
> I encountered a question about the size of hash table:
> 
> LVS_2.2.13-HOWTO said:
> "The hash table is used to speed up the connection lookup. The connection
> entry is used keep state so that packets belongs to a connection from
> the client will be sent to the server previously allocated for the
> connection. The default number of connections (== number of entries
> in hash table) is 2^12. This can be configured when building the kernel
> Makefile."
> 
>     I find some files about this:
> include/net/ip_vs.h
> net/ipv4/ip_masq.c
> net/ipv4/ip_vs.c
>   but  I cannot find '2^12' and where can I change this parameter.

CONFIG_IP_MASQUERADE_VS_TAB_BITS=#value   /* in .config of
/usr/src/linux/
 
> Suppose there are 6000 connections to Director at the same time,
> and the ppc is default 360s,  what should this parameter be set to ?
> and what is the upper limit of this parameter? 2^18?

yes, although I once ran into problems with kernel panics having 2^18,
but 2^17 was always safe for me.
 
Regards,

Roberto Nibali, ratz