Monitoring a large log file in C#

Question

I have to monitor a large log file during the day with C#. The size goes up to 200-300 MB for a day.
What is the most efficient way to analyze it?
The file is locked by the producing program. Preferably I would either have a read which realises that lines have been added or would read backwards.

score 3 · Accepted Answer · answered Jul 16 '10 at 10:23

3

A combination of MemoryMappedFile and FileSystemWatcher should do the trick.

answered Jul 16 '10 at 10:23

Oliver

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score 1 · Answer 2 · edited Nov 19 '12 at 14:01

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You will never achieve good results with C#.

I created application in C++ and I used MFC String to search 1GB file.
It takes about 15-20 seconds. After that I used char type and it takes about 3 sec!!!!

C# has lot of overhead and if you need really fast solution, use C++ and TCHAR, char, data type.

edited Nov 19 '12 at 14:01

bipen

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answered Nov 19 '12 at 13:35

opis

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score 0 · Answer 3 · answered Jul 16 '10 at 09:58

0

Change log rotation to a smaller value and then process the rotated logs - or - Process the whole log file the first time and remember the fileoffset / line for the next checking interval.

answered Jul 16 '10 at 09:58

DCA

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Monitoring a large log file in C#

3 Answers3