gmirror + gjournal and write cache on drives enabled

[Kai Gallasch]

Hi.

I'm currently installing a server with 4 x SAS JBOD connected to an mpt(4) pseudo-raid controller.

# gmirror status
      Name    Status  Components
mirror/gm0  COMPLETE  da0
                      da1
/dev/mirror/gm0s1a.journal    /
/dev/mirror/gm0s1d.journal    /var
/dev/mirror/gm0s1e.journal    /usr
/dev/mirror/gm0s1f.journal    /usr/local
/dev/mirror/gm0s1g.journal    /usr/src
/dev/mirror/gm0s1h.journal    /usr/obj

in gjournal(8) I read:

   "When gjournal is configured on top of gmirror(8) or graid3(8) providers,
   it also keeps them in a consistent state, thus automatic synchronization
   on power failure or system crash may be disabled on those providers."

Is this statement also true, if the JBODs have their write-cache enabled?
If yes, I'd gladly "gmirror configure -F" to avoid a full sync in case of a server crash, power loss, etc.

Kai.