Results of testing Codepoint Prediction for Patch/Subset

I've gotten the complete results for adding codepoint prediction to the
patch/subset transfer methods and re-running the simulations. You can find
a detailed writeup of the results here:
https://docs.google.com/document/d/1u-05ztF9MqftHbMKB_KiqeUhZKiXNFE4TRSUWFAPXsk/edit?usp=sharing

Executive summary from the doc:

"Codepoint prediction, that is adding extra non-requested codepoints to a
font augmentation response was tested with the progressive font enrichment
simulations to see if it could improve performance and close the gaps where
progressive font enrichment performed worse than existing transfer methods.

The result of the simulations showed that for all three script categories
using codepoint prediction was able to lower costs enough to tie or beat
existing transfer methods for all connection types other than Mobile 2G and
the slowest variant of Mobile 3G. This comes at the cost of sending more
bytes, but still sends less bytes than existing transfer methods.

CJK scripts benefited the least from prediction. Arabic, Indic, Latin,
Cyrllic, Greek, and Thai saw more improvements.  For those scripts
prediction closed the performance gap between existing font transfer
methods for many connection types.

Prediction was not beneficial in all cases. For some script and network
conditions combinations it increased overall cost. If prediction is to be
used it should be selectively enabled based on the script and client
network capabilities.

Lastly the simulations demonstrated that comparing the total cost of
incremental optimal vs one font optimal method can help point us to where
using prediction will likely lead to improvements in cost. The one font
optimal method provides a lower bound for the performance of a perfect
prediction algorithm."

Received on Tuesday, 21 July 2020 22:54:45 UTC