CRC Errors on download
|Category:||General||Estimated time:||0.50 hour|
|Target version:||010 - Next Major Public Release 1.xxx|
Several users are reporting frequent CRC errors on downloads (either identified by the MD5 from the Host or by unrar). Redownload eliminates the problem. I have excluded the known problems. One user reported that he did a binary comparison and only the last byte was different. These users had Max.Con.=1 and in some cases were only downloading one file at a time.
I do not have the evidence yet, but I suspect that the problem is downloading chunks that do not start at a word boundary (4 or 8 bytes, depending on the OS and version).
When a TCP time-out occurs (but the host is keeping the session open), JD performs a new HTTP connection beginning at the next byte. I believe we should round down the beginning byte of each chunk request to a multiple of 8 bytes (AND the start byte with (-8)).
I do not know the architecture of the host plugins well enough to estimate work hours. If the reconnections are in the plugins, this is a big job (on an as changed basis, except for the top sites). If the reconnections are in JD, this should take at most 1/2 hour to fix.