The attention to detail at Google is remarkable. Jeff gleefully described the various index compression techniques they created and used over the years. He talked about how they finally settling on a format that grouped 4 delta of positions together in order to minimize the number of shift operations needed during decompression. They paid attention to where their data was laid out on disk, keeping the data they needed to stream over quickly always on the faster outer edge of the disk, leaving the inside for cold data or short reads. They wrote their own recovery for errors with non-parity memory. They wrote their own disk scheduler. They repeatedly modified the Linux kernel to meet their needs. They designed their own servers with no cases, then switched to more standard off-the-rack servers, and now are back to custom servers with no cases again.
You think?
Gregor J. Rothfuss 