Subject Re: [IB-Architect] Fan out and processor cache friendliness
Author Jim Starkey
At 09:01 AM 4/8/00 +1000, Jan Mikkelsen wrote:
>
>>Something that I've been sorely tempted to do is to use a
>>variable length prefix/length fields to support keys greater
>>than 255 bytes. It would be computationally cheaper to make
>>the prefix/length fields two bytes each, but the wasted bits
>>bug me. A variable length encoding could store lengths up
>>to 127 in a single byte (which is really just about everything),
>>requiring a second byte for only very long keys at the expense
>>of twice the number of machine instructions per node.
>
>
>In this context machine instructions really are free on modern machines,
>because with prefetching, you can do work while you wait for the next cache
>line to become L1 cache resident. Variable length encodings are becoming
>advantageous.
>

OK, if it rains Sunday, I'll code it up and give it a try. I
absolutely hate numerical limitations.

Jim Starkey