Opened at 2010-08-15T06:14:25Z
Last modified at 2011-04-11T17:01:59Z
#1180 new defect
put more DYHBs into flight at once when K is larger — at Initial Version
| Reported by: | zooko | Owned by: | |
|---|---|---|---|
| Priority: | major | Milestone: | soon |
| Component: | code-network | Version: | 1.8β |
| Keywords: | easy immutable download performance regression | Cc: | |
| Launchpad Bug: |
Description
As mentioned in comment:8:ticket:448, the new downloader code in v1.8.0 will put at most 10 DYHBs into flight at once. This is perfect when K=3, but as K gets larger it is increasingly likely that the hardcoded limit of 10 will induce delay at the beginning of a download or cause the downloader to overlook a better-performing server. As Brian suggested on #448, a better limit would be something like K * 3.
(Note: everyone that I know of uses the default settings of K=3, M=10. The theoretical maximum value of K is 256. I think there might be other problems with using K greater than about 100, such as a worse rate of a storage server failing during your download, but I'm not sure.)
