Caches and Eviction Policies

Caching systems are finite in size. So what happens when your cache is filled with objects ? No more objects ? Game over ? Hopefully, no. Most modern caches have some form of replacement or eviction policy. What means that based on some criteria, it’ll figure out what objects to throw out the window so...
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TCP splicing

This looks promising and potentially wickedly awesome: http://www.linuxvirtualserver.org/software/tcpsp/ Has anyone played with this yet in a production environment ?...
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5 Little Known Things

Ok, Geva Perry tagged me so here goes: 1. After graduating from Umass/Amherst with a Mechanical Engineering degree, I worked at the Volpe National Transportation Systems Center, doing side-impact crashworthiness research for the NHTSA. We ran transient dynamic finite-element analysis simulations using LS-DYNA and rigid-body simulations with MADYMO3D. This is where I learned UNIX, because...
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TCP bug

when you see this: (loaded box, lots of network, 2.6.9.x kernel, etc.) Dec 21 04:05:58 hostname kernel: ————[ cut here ]———— Dec 21 04:05:58 hostname kernel: kernel BUG at net/ipv4/tcp_output.c:927! Dec 21 04:05:58 hostname kernel: invalid operand: 0000 [#1] Dec 21 04:05:58 hostname kernel: SMP do this: Add to sysctl.conf: net.ipv4.tcp_retrans_collapse = 0...
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