good/best practices for gmirror and gjournal on a pair of disks?

[George Hartzell]

Adam McDougall writes:
 > [...]
 > I believe gjournal uses 1G for journal (2x512) which seemed to be 
 > sufficient on all of the systems where I have used the default, but I 
 > quickly found that using a smaller journal is a bad idea and leads to 
 > panics that I was unable to avoid with tuning.  Considering 1G was such 
 > a close value, I chose to go several times above the default journal 
 > size (disk is cheap and I want to be sure) but I ran into problems using 
 > gjournal label -s (size) rejecting my sizes or wrapping the value around 
 > to something too low. [...]

I also stumbled on this and was unable to find any mention of it in
the pr database.  One of my todo items is to make sure I'm not messing
up somehow, dig further into the PR db for an existing report, and
file one if I can't find one?

I tried -s 2147483648 and it was found to be "too small".  A quick
read of the source led me to find that jsize is an intmax_t and that
gctl_get_intmax()  should be returning an intmax_t and that intmax_
ought to be an __int64_t (I'm on amd64), which left me confused.

Has anyone else seen/reported a problem with gjournal -s and values >
1G?

g.