How often does A/UX sync the file system?
A/UX 3.0 performs a sync every minute. It’s done by ‘init’ and the frequency can’t be changed. A/UX 3.0.[1|2] does one every 30 seconds; cached blocks older than 30 seconds are flushed, therefore a block can be resident for between 30 and 59 seconds. If you want, you can use ‘adb’ to change the value of ‘syncdsleep’ to the number of seconds to sleep between flushes. Blocks older than that will be flushed. A/UX 3.1.x peforms a sync every second and flushes blocks that are older than 30 seconds (i.e. a block can be resident for 1 to 31 seconds). You can alter this by using ‘adb’ to change ‘syndperiod’ to the timeout age (how old the block can be before it’s flushed) and ‘syncdsample’ to the wakeup period; by default, ‘syncdperiod’ is 30 and ‘syncdsample’ is 1. From A/UX 3.0.1 onward, the kernel process ‘syncd’ can be seen via ‘ps’.
A/UX 3.0 performs a sync every minute. It’s done by ‘init’ and the frequency can’t be changed. A/UX 3.0.1/3.0.2 does one every 30 seconds; cached blocks older than 30 seconds are flushed, therefore a block can be resident for between 30 and 59 seconds. If you want, you can use ‘adb’ to change the value of ‘syncdsleep’ to the number of seconds to sleep between flushes. Blocks older than that will be flushed. A/UX 3.1.x peforms a sync every second and flushes blocks that are older than 30 seconds (i.e. a block can be resident for 1 to 31 seconds). You can alter this by using ‘adb’ to change ‘syndperiod’ to the timeout age (how old the block can be before it’s flushed) and ‘syncdsample’ to the wakeup period; by default, ‘syncdperiod’ is 30 and ‘syncdsample’ is 1. From A/UX 3.0.1 onward, the kernel process ‘syncd’ can be seen via ‘ps’.
