On Mon, Nov 26, 2001 at 09:28:03AM -0800, Brian Pane wrote: >... > * Rather than creating a temporary brigade for concatenation, > create a heap bucket. Make it big enough to hold 8KB. Pop > the small buckets from the brigade, concatenate their contents > into the heap bucket, and push the heap bucket onto the brigade. > > * If we end up in the concatenation again during the foreach loop > through the brigade, add the small buckets to the end of the > previously allocated heap bucket. If the heap bucket size is > about to exceed 8KB, stop. > > Comments?
You could actually scan the whole brigade and replace small buckets with a large heap bucket. For example: compress the first 20 5-byte buckets into a single 100-byte bucket, skip the 10k file bucket, then compress the next 50 10-byte buckets into a 500-byte bucket. The rule of thumb is simply "stop concatenating if you find a bucket bigger than your threshold." Whether you skip over those looking for more is a different question. Note that apr_brigade_write() is fine if you're writing to the "end" of a brigade. It doesn't work well "within", and it could also pose problems if you trigger its flushing behavior. That said, if you're concatenating and *moving* buckets (i.e. from the input brigade to a holding brigade), then you're always writing at the end. Also: why would this ever "exceed 8KB" ?? If that was the case, then you'd just send the brigade to the network rather than try to hold onto it. Finally: since you probably know the size of your concat-buffer, then you can allocate the heap bucket to be the proper size, rather than use a default 8k heap bucket. Cheers, -g -- Greg Stein, http://www.lyra.org/
