Amos Jeffries wrote:
>On 6/04/20 12:57 pm, Stephen R. van den Berg wrote:
>> You mean because it will cost an extra clockcycle on decode per character?
>> That will only be relevant for very large sequences of base64 characters.

>How are you defining "large" here?

>Base64 data inputs can be any size. Megabytes are not uncommon in
>network messaging.

That's what I meant.

>> And the sequences are that large, the speed to decode becomes RAM-access
>> bound; in which case there will be plenty of spare CPU cycles.  This
>> essentially makes the extra "if" cost-free.

>For this type of situation we should expect the L1/L2 cache lines to be
>loaded by the time they are needed. Delays will most likely be from
>interruptions to the decode thread, or less likely; code or table size
>causing swapouts from the L1/L2 caches.

Ok, I stand corrected.  I just checked the RAM subsystem speeds of current
systems, and I find that 250GB/s is not uncommon.  In that case, every
extra clockcycle will hurt.  I'll retract the tablesize optimisation.
-- 
Stephen.
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