reported checkpoint duration times

hi, in online 7.x, it reports the checkpoint duration in the logfile. i am seeing some very strange times, that i haven't been able to figure out. one of the things i need to know is this: if a user is in a critical section of code, the checkpoint cannot take place, and online will wait until the user is out of a critical section. is that time included in the checkpoint duration time? so if the system goes to do a checkpoint, and then must wait 5 seconds for the user to come out of a critical section, is that 5 seconds included in the time reported for the duration? this is an example: 07:22:55 Checkpoint Completed: duration was 0 seconds. 07:29:16 Logical Log 11083 Complete. 07:29:18 Logical Log 11083 - Backup Started 07:29:19 Logical Log 11083 - Backup Completed 07:32:25 Logical Log 11084 Complete. 07:32:28 Logical Log 11084 - Backup Started 07:32:29 Logical Log 11084 - Backup Completed 07:32:58 Checkpoint Completed: duration was 3 seconds. 07:43:09 Checkpoint Completed: duration was 11 seconds. 07:53:12 Checkpoint Completed: duration was 2 seconds. 08:03:13 Checkpoint Completed: duration was 1 seconds. 08:04:23 Logical Log 11085 Complete. 08:04:24 Logical Log 11085 - Backup Started 08:04:25 Logical Log 11085 - Backup Completed our system has relatively few writes, and the logfile is 10mb. i can't imagine that the logfile was full enough and there were enough dirty buffers that it took 11 seconds to flush them all, especially as in that time not a single log file filled up. pertinent onconfig parameters are: CLEANERS 10 # Number of buffer cleaner processes LRUS 10 # Number of LRU queues LRU_MAX_DIRTY 15 # LRU percent dirty begin cleaning limit LRU_MIN_DIRTY 5 # LRU percent dirty end cleaning limit in the middle of the day, during heavy processing, i will go through a day where my durations are 0-1 seconds. today for instance, they have been anywhere from 0 to 15 seconds. and i'm not sure where the bottleneck is. any thoughts? mickm