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Increasing the size of the NTFS Change Journal

Article ID: 24
Last updated: 20 Mar, 2012

The default size for the NTFS change journal is around 1 MB which is too small for large servers with many (1 million+) files.

To query the current value, run the following command as an Administrator: fsutil usn queryjournal C: (replace C: with the desired drive). 

The result will look something like this:
Usn Journal ID   : 0x01cae79a4530d62e
First Usn        : 0x0000000000000000
Next Usn         : 0x0000000000000108
Lowest Valid Usn : 0x0000000000000000
Max Usn          : 0x00000fffffff0000
Maximum Size     : 0x0000000000100000
Allocation Delta : 0x0000000000040000

Take the hex value Maximum Size and convert it to decimal to get the current CJ size in bytes. I.e. 100,000 hex = 1,048,576 = 1 MB.

To increase the CJ size for a particular volume, run the following command (set the Maximum Size to at least 32 MB and the AllocationDelta to an 8th of that) i.e: fsutil usn createjournal m=33554432 a=4194304 C:

Repeat for all large drives you want to back up. Confirm the setting is active by querying the journal size again.

The table below includes the various figures needed to change the CJ to different amounts.

Files

Maximum Size (m) in bytes

AllocationDelta (a) in bytes

m (MB)

m (hex)

a (hex)

400 000 536 870 912 67 108 864 512 20000000  4000000
600 000 805 306 368 100 663 296 768 30000000  6000000
800 000 1 073 741 824 134 217 728 1 024 40000000  8000000
1 000 000 1 342 177 280 167 772 160 1 280 50000000  A000000
1 200 000 1 610 612 736 201 326 592 1 536 60000000  C000000
1 400 000 1 879 048 192 234 881 024 1 792 70000000  E000000
1 600 000 2 147 483 648 268 435 456 2 048 80000000  10000000
1 800 000 2 415 919 104 301 989 888 2 304 90000000  12000000
2 000 000 2 684 354 560 335 544 320 2 560 A0000000  14000000
2 200 000 2 952 790 016 369 098 752 2 816 B0000000  16000000
2 400 000 3 221 225 472 402 653 184 3 072 C0000000  18000000
2 600 000 3 489 660 928 436 207 616 3 328 D0000000  1A000000
2 800 000 3 758 096 384 469 762 048 3 584 E0000000  1C000000
3 000 000 4 026 531 840 503 316 480 3 840 F0000000  1E000000
3 200 000 4 294 967 296 536 870 912 4 096 100000000  20000000

Reference:
http://technet.microsoft.com/en-us/library/cc788042(WS.10).aspx

Article ID: 24
Last updated: 20 Mar, 2012
Revision: 1
Views: 22854
Comments: 0
Posted: 29 Apr, 2010 by Marais D.
Updated: 20 Mar, 2012 by -- .
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