From: Abhijeet Rastogi abhijeet.1989@gmail.com
commit 04292c695f82b6cf0d25dd5ae494f16ddbb621f6 upstream.
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.1631289...
Signed-off-by: Abhijeet Rastogi abhijeet.1989@gmail.com Acked-by: Julian Anastasov ja@ssi.bg Acked-by: Simon Horman horms@kernel.org Signed-off-by: Pablo Neira Ayuso pablo@netfilter.org Cc: Allen Pais apais@linux.microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- net/netfilter/ipvs/Kconfig | 27 ++++++++++++++------------- net/netfilter/ipvs/ip_vs_conn.c | 4 ++-- 2 files changed, 16 insertions(+), 15 deletions(-)
--- 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"
--- 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;