We started inserting new data into more or less random collections but the lock ratio was very high. (>100% with just 60 inserts/s)

After restart of mongo we started with inserts again and after few minutes the following error occurred in the log and mongo started allocating new db files like crazy. I managed to stop it before it filled the whole disk but it allocated some 50 new files. The process was stopped correctly.

log:

Thu Apr 28 17:15:05 [conn4] insert rcware.values330 140ms
Thu Apr 28 17:15:08 [conn4] insert rcware.values321 187ms
Thu Apr 28 17:15:08 [conn4] insert rcware.values323 187ms
Thu Apr 28 17:15:09 [conn4] insert rcware.values302 109ms
Thu Apr 28 17:15:14 [conn4] VirtualProtect failed 66616814000000 4000000 errno:1455 The paging file is too small for this operation to complete.
Thu Apr 28 17:15:14 [conn4] rcware.values1850 Assertion failure false db\mongommf.cpp 72
Thu Apr 28 17:15:14 [conn4] rcware.values1850 caught assertion update unindex rcware.values1850.$r_1_t_1_g_1
Thu Apr 28 17:15:14 [conn4] VirtualProtect failed 66616814000000 4000000 errno:1455 The paging file is too small for this operation to complete.
Thu Apr 28 17:15:14 [conn4] rcware.values1850 Assertion failure false db\mongommf.cpp 72
Thu Apr 28 17:15:14 [conn4] rcware.values1850 caught assertion update index rcware.values1850.$r_1_t_1_g_1 0 assertion db\mongommf.cpp:72
Thu Apr 28 17:15:14 [conn4] VirtualProtect failed 45494714000000 4000000 errno:1455 The paging file is too small for this operation to complete.
Thu Apr 28 17:15:14 [conn4] rcware.values1850 Assertion failure false db\mongommf.cpp 72