netdev - SFQ depth limit

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Date:	Sat, 28 Jun 2008 22:02:59 +0300
From:	Denys Fedoryshchenko <denys@...p.net.lb>
To:	netdev@...r.kernel.org
Subject: SFQ depth limit

Hi

Is there any particular reason to limit SFQ depth to 127 packets?
#define SFQ_DEPTH               128

Just to buffer data on 1Gbps rate for 1 second i need 87k packets, let's say just for 10ms buffer - 873 packets, which is out of limit.
Also if i will use external SFQ flow classifier made by Patrick McHardy, let's say for 4096 ip's, i am not sure also if i hit this limit. 
As i understand, if i increase it - it will increase also data structures size in memory.

And probably i hit some unknown issue.
Example:
tc qdisc add dev eth0 handle 1 root sfq
tc filter add dev eth0 protocol ip pref 1 parent 1: handle 1 flow hash keys dst divisor 1024
MegaRouterCore-KARAM ~ #tc -s qdisc show dev eth0
qdisc sfq 1: root limit 127p quantum 1514b
 Sent 12062 bytes 89 pkt (dropped 3, overlimits 0 requeues 0)
 rate 0bit 0pps backlog 0b 0p requeues 0
MegaRouterCore-KARAM ~ #tc -s qdisc show dev eth0
qdisc sfq 1: root limit 127p quantum 1514b
 Sent 12824 bytes 94 pkt (dropped 3, overlimits 0 requeues 0)
 rate 0bit 0pps backlog 0b 0p requeues 0
MegaRouterCore-KARAM ~ #tc -s qdisc show dev eth0
qdisc sfq 1: root limit 127p quantum 1514b
 Sent 13586 bytes 99 pkt (dropped 3, overlimits 0 requeues 0)
 rate 0bit 0pps backlog 0b 0p requeues 0
MegaRouterCore-KARAM ~ #tc -s -d qdisc show dev eth0
qdisc sfq 1: root limit 127p quantum 1514b flows 127/1024
 Sent 15552 bytes 114 pkt (dropped 8, overlimits 0 requeues 0)
 rate 0bit 0pps backlog 0b 0p requeues 0
MegaRouterCore-KARAM ~ #tc -s -d qdisc show dev eth0
qdisc sfq 1: root limit 127p quantum 1514b flows 127/1024
 Sent 16232 bytes 118 pkt (dropped 9, overlimits 0 requeues 0)
 rate 0bit 0pps backlog 0b 0p requeues 0

after that host is dead...



-- 
------
Technical Manager
Virtual ISP S.A.L.
Lebanon
--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html