What is a rollover logfile ?

Under the normal system every time you add an entry to a logfile, it is appended to the end of a file, and the file gets bigger. This causes 2 major problems :-

  1. You have to shorten or delete the logfile every so often.
  2. The logfile gets very fragmented.

Using a program call 'MakeRollOver' you can create a new logfile. When it is created you should choose how many disks blocks you wish to allocate to the logfile. This space is allocated immediately although the size will show as 0. As data is appended to the file it will grow in size until it reaches the size you allocated. After this point data will still be appended to the end of logfile, but the file will not get any bigger. This is achieved by PFS-2 removing the oldest entries from the start of the file.

Note that when you create a rollover file you specify the number of blocks to allocate. Not the number of bytes !

Note also that rollover files are converted to normal files by all known backup systems. If you ever have to restore you will have to rename the file, create the rollover version and copy the data back into it. Remember to delete the temporary copy !