linux-kernel - Loopback and Nagle's algorithm

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 for Android: free password hash cracker in your pocket

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

Date:	Mon, 11 Apr 2011 22:37:49 -0400
From:	"Adam McLaurin" <lkml@...tas.net>
To:	linux-kernel@...r.kernel.org
Subject: Loopback and Nagle's algorithm

I understand that disabling Nagle's algorithm via TCP_NODELAY will
generally degrade throughput. However, in my scenario (150 byte
messages, sending as fast as possible), the actual throughput penalty
over the network is marginal (maybe 10% at most).

However, when I disable Nagle's algorithm when connecting over loopback,
the performance hit is *huge* - 10x reduction in throughput.

The question is, why is disabling Nagle's algorithm on loopback so much
worse w.r.t. throughput? Is there anything I can do to reduce the
incurred throughput penalty?

Thanks,
Adam
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/