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Why is there a 2GB file size limit on x64 Win7 with 4GB RAM


I have the 64 bit version of Wireshark installed Version 1.4.5 (SVN Rev 36650 from /trunk-1.4) on Win7 Ultimate with 4GB of RAM. I am trying to load a 1.3GB PCAP file. When Wireshark gets to 2GB of memory allocated even though there is 1GB free it crashes.

I was under the impression that the x64 version of Wireshark did not have any limitations on memory. Any ideas?

asked 18 Apr '11, 18:32

gff1stof3's gravatar image

accept rate: 0%

One Answer:


Given that the file is only 1.3GB, presumably you mean "2GB address space size limit" rather than "2GB file size limit". (There's a 2GB file size limit in 1.4.5 because, in all Ethereal/Wireshark releases prior to 1.5, and in the 1.5 (trunk) until recently, the calls used to seek into the capture file used a 32-bit file offset, even on most 64-bit platforms, including Windows.)

I'd report that as a bug at the Wireshark Bugzilla. Please give as much information as you can, including any error information from Windows.

answered 18 Apr '11, 18:37

Guy%20Harris's gravatar image

Guy Harris ♦♦
accept rate: 19%

Bug 5979 is now tracking this issue.

(01 Jun '11, 06:45) JeffMorriss ♦