From: Holger Eitzenberger Date: Sat, 4 Feb 2006 10:13:14 +0000 (-0800) Subject: [NETFILTER]: ULOG/nfnetlink_log: Use better default value for 'nlbufsiz' X-Git-Tag: v2.6.16-rc3~146^2~10 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=c2db292438c20c3f13db6e5563e0ce5b449bedac;p=linux-2.6 [NETFILTER]: ULOG/nfnetlink_log: Use better default value for 'nlbufsiz' Performance tests showed that ULOG may fail on heavy loaded systems because of failed order-N allocations (N >= 1). The default value of 4096 is not optimal in the sense that it actually allocates _two_ contigous physical pages. Reasoning: ULOG uses alloc_skb(), which adds another ~300 bytes for skb_shared_info. This patch sets the default value to NLMSG_GOODSIZE and adds some documentation at the top. Signed-off-by: Holger Eitzenberger Signed-off-by: Patrick McHardy Signed-off-by: David S. Miller --- diff --git a/net/bridge/netfilter/ebt_ulog.c b/net/bridge/netfilter/ebt_ulog.c index ce617b3dbb..dbbf9f673b 100644 --- a/net/bridge/netfilter/ebt_ulog.c +++ b/net/bridge/netfilter/ebt_ulog.c @@ -46,7 +46,7 @@ #define PRINTR(format, args...) do { if (net_ratelimit()) \ printk(format , ## args); } while (0) -static unsigned int nlbufsiz = 4096; +static unsigned int nlbufsiz = NLMSG_GOODSIZE; module_param(nlbufsiz, uint, 0600); MODULE_PARM_DESC(nlbufsiz, "netlink buffer size (number of bytes) " "(defaults to 4096)"); diff --git a/net/ipv4/netfilter/ipt_ULOG.c b/net/ipv4/netfilter/ipt_ULOG.c index 641dbc4776..2fe64133bb 100644 --- a/net/ipv4/netfilter/ipt_ULOG.c +++ b/net/ipv4/netfilter/ipt_ULOG.c @@ -35,6 +35,10 @@ * each nlgroup you are using, so the total kernel memory usage increases * by that factor. * + * Actually you should use nlbufsiz a bit smaller than PAGE_SIZE, since + * nlbufsiz is used with alloc_skb, which adds another + * sizeof(struct skb_shared_info). Use NLMSG_GOODSIZE instead. + * * flushtimeout: * Specify, after how many hundredths of a second the queue should be * flushed even if it is not full yet. @@ -76,7 +80,7 @@ MODULE_ALIAS_NET_PF_PROTO(PF_NETLINK, NETLINK_NFLOG); #define PRINTR(format, args...) do { if (net_ratelimit()) printk(format , ## args); } while (0) -static unsigned int nlbufsiz = 4096; +static unsigned int nlbufsiz = NLMSG_GOODSIZE; module_param(nlbufsiz, uint, 0400); MODULE_PARM_DESC(nlbufsiz, "netlink buffer size"); diff --git a/net/netfilter/nfnetlink_log.c b/net/netfilter/nfnetlink_log.c index e10512e229..50787af86d 100644 --- a/net/netfilter/nfnetlink_log.c +++ b/net/netfilter/nfnetlink_log.c @@ -37,7 +37,7 @@ #include "../bridge/br_private.h" #endif -#define NFULNL_NLBUFSIZ_DEFAULT 4096 +#define NFULNL_NLBUFSIZ_DEFAULT NLMSG_GOODSIZE #define NFULNL_TIMEOUT_DEFAULT 100 /* every second */ #define NFULNL_QTHRESH_DEFAULT 100 /* 100 packets */