Nmap Development mailing list archives
Re: [Zenmap] Slow "Open" for large files
From: Daniel Miller <bonsaiviking () gmail com>
Date: Sun, 8 Jun 2014 11:30:58 -0500
Jay, Thanks for following up on this! This patch is exactly what I was looking for. It passes my checks; please commit it at your earliest convenience. Dan On Sun, Jun 8, 2014 at 7:58 AM, Jay Bosamiya <jaybosamiya () gmail com> wrote:
Hi All! While I was testing things for my other patch (the MemoryError one), I came upon this rather strange thing. A scan that I had run took 30 seconds to run, about a second to save, but hours to load. The "Open" option was too slow for large files! Some analysis showed that the Open option was using string concatenation and this made the algorithm quadratic in time complexity. (Thanks Dan for pointing out that string concatenation is slow in Python). Modifying this to use StringIO immediately improves the speed. The same file opened in under half a minute!!! Attached is the patch for the same. I had to refactor some other parts of the code for zenmap/zenmapCore/NmapParser.py too (since _nmap_output is used in some places where nmap_output should be used). I have tested this patch and there seems to be no problem. Feedback is welcome. Cheers, Jay PS: The command I used to generate the large file is "nmap --packet-trace -r --top-ports 1000 127.0.0.1/24". The generated xml file (using "Save" from Zenmap) is about 20 MB in size! _______________________________________________ Sent through the dev mailing list http://nmap.org/mailman/listinfo/dev Archived at http://seclists.org/nmap-dev/
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Current thread:
- [Zenmap] Slow "Open" for large files Jay Bosamiya (Jun 08)
- Re: [Zenmap] Slow "Open" for large files Daniel Miller (Jun 08)
- Re: [Zenmap] Slow "Open" for large files Jay Bosamiya (Jun 09)
- Re: [Zenmap] Slow "Open" for large files Jacek Wielemborek (Jun 09)
- Re: [Zenmap] Slow "Open" for large files Jay Bosamiya (Jun 09)
- Re: [Zenmap] Slow "Open" for large files Daniel Miller (Jun 09)
- Re: [Zenmap] Slow "Open" for large files Jay Bosamiya (Jun 09)
- Re: [Zenmap] Slow "Open" for large files Jay Bosamiya (Jun 09)
- Re: [Zenmap] Slow "Open" for large files Daniel Miller (Jun 08)