48585 - Double downloading of messages

Status: VERIFIED DUPLICATE of bug 22034

(MailNews Core :: Networking: IMAP, defect, P3)

Description

[tenthumbs]

Testing against my localhost IMAP server on Linux (UW IMAP-2000-RC4) I noticed
that if I double-click on a message with an image attachment so that a new
window opens, then Mozilla downloads the entire message and then immediately
downloads it again. This is with a ~3MB image so the entire message is ~4MB
after encoding.

On a modem connection, this would be extremely poor.

Comment 1

[lchiang]

Probably the same as http://bugzilla.mozilla.org/show_bug.cgi?id=22034.

Comment 2

[tenthumbs]

Possibly, but this one depends on partial body fetches.

If I create a 2000x2000 image of a solid color it is onlg 581 bytes as a PNG but
~63K as a JPEG. If I attach the PNG to a short message Mozilla transfers the
message in one lump and that's all. If I attach the JPEG (which is ~87K after
encoding) then Mozilla does partial transfers and downloads it twice.

Now 2000x2000 *is* rather extreme but I can see the same thing with a 1024x768
screenshot as a JPEG.

Comment 3

[tenthumbs]

Actually, it double downloads the entire message so I'm changing the summary to
so indicate.

The dimensions of an image seem to make no difference. A 488x600 RGB+alpha PNG,
which is ~500K, shows the same problem.

Comment 4

[Scott MacGregor]

after we've download an individual mime part, we must not be realizing that it's
in the disk cache. Probably due to differences in the url structure which is
used to determine cache hits. 

Comment 5

[lchiang]

per mail triage, mark dup of 22034

*** This bug has been marked as a duplicate of 22034 ***

Comment 6

[Karen Huang]

Verified as duplicate.