Performance regression with ftp protocol when uploading in image mode

Hi,

A customer is reporting slow Ftp upload in Java 7, versus Java 6.

<<

In our application, we are using URL.openConnection() to open the FTP connection. We would like to know if there is a way to open the buffer Size as mentioned in the URL below or could we do something else to make the “ java FTP” file transfer faster ?

http://stackoverflow.com/questions/14000341/why-is-ftp-upload-slow-in-java-7"

>>

The last version tested that does not worked is 7u15. The version
that is working is 6u33.
Solaris 10

No testcase, but here is the snippet:

 URL lUrl = new URL(aInContextURL, aInFtpUrl);
lUrl.openConnection().getOutputStream();

wireshark snippet when using jdk_1.7.0_15 - BAD case

1205826 728.057224 135.121.1.171 135.121.1.60 FTP-DATA FTP Data: 220 bytes
1205827 728.059320 135.121.1.171 135.121.1.60 FTP-DATA FTP Data: 1460 bytes
1205828 728.059327 135.121.1.171 135.121.1.60 FTP-DATA FTP Data: 1 bytes
1205829 728.059331 135.121.1.60 135.121.1.171 TCP 51748 > 48997 [ACK] Seq=1 Ack=527417331 Win=49640 Len=0
1205830 728.059403 135.121.1.171 135.121.1.60 FTP-DATA FTP Data: 14 bytes
1205831 728.061662 135.121.1.171 135.121.1.60 FTP-DATA FTP Data: 1460 bytes
1205832 728.061668 135.121.1.171 135.121.1.60 FTP-DATA FTP Data: 1 bytes

1,205,871 packets to send 503M file using ftp

wireshark snippet when using jdk_1.6.0_33 - GOOD case

50 0.197849 135.121.1.60 135.121.1.23 TCP 25616 > 53511 [ACK] Seq=1 Ack=10221 Win=49640 Len=0
51 0.197965 135.121.1.23 135.121.1.60 FTP-DATA FTP Data: 1460 bytes
52 0.198089 135.121.1.23 135.121.1.60 FTP-DATA FTP Data: 1460 bytes
53 0.198211 135.121.1.23 135.121.1.60 FTP-DATA FTP Data: 1460 bytes
54 0.198334 135.121.1.23 135.121.1.60 FTP-DATA FTP Data: 1460 bytes

397,919 packets to send 462M file using ftp


Seeking advice, pointers, further debugging tips.


Thank you,

Kim