One thing to consider too, and maybe it's off-topic, but if you hand over the optimization work to someone like Kraken.io, then you have all the network overhead to worry about and that might make ~70ms into several seconds.
Yeah, I wouldn't recommend that as a general strategy but my rationale was roughly that while I have a CDN it has a hit rate somewhere around 60% and so all but the consistently most popular content refreshes more regularly than the TTLs. Having a queued worker looking at the more popular images and optimizing them really aggressively would be nice both for gradually improving things over time.
I agree, though, that this is an edge case. The first thing I was looking into doing was much easier, optimizing the DZI files we use with OpenSeadragon (http://openseadragon.github.io) since those are already generated off-line and stored durably.
The other thing I wanted to look into was the latency of calling a binary vs. doing this in process to see if it'd be worth using a cffi binding to optimize the images in memory (Pillow -> mozjpeg -> disk).
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One thing to consider too, and maybe it's off-topic, but if you hand over the optimization work to someone like Kraken.io, then you have all the network overhead to worry about and that might make ~70ms into several seconds.
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Yeah, I wouldn't recommend that as a general strategy but my rationale was roughly that while I have a CDN it has a hit rate somewhere around 60% and so all but the consistently most popular content refreshes more regularly than the TTLs. Having a queued worker looking at the more popular images and optimizing them really aggressively would be nice both for gradually improving things over time. I agree, though, that this is an edge case. The first thing I was looking into doing was much easier, optimizing the DZI files we use with OpenSeadragon (http://openseadragon.github.io) since those are already generated off-line and stored durably. The other thing I wanted to look into was the latency of calling a binary vs. doing this in process to see if it'd be worth using a cffi binding to optimize the images in memory (Pillow -> mozjpeg -> disk).