Extend default post lock expiration from 120 to 150 sec.

[azaozz]

In some cases when user A is currently editing a post but takes a break or the browser window is blurred (heartbeat runs on 2 min. interval) and user B opens the same post for editing and waits on the Edit Post screen (the "Post locked" modal is shown, heartbeat runs at 15 sec. interval), user B may take the post lock automatically, without clicking "Take over".

[nacin]

Is another option to speed up heartbeat a bit?

[azaozz]

Yeah, can speed it up to 100 sec. interval instead of 120 sec. when the window is blurred/user is away. This is a "non-fatal false positive". Worst case scenario is user A will get the "Post lock taken over" dialog while user B would still be waiting on the Edit Post screen with "Post is locked" dialog open.

[nacin]

Replying to azaozz:

Yeah, can speed it up to 100 sec. interval instead of 120 sec. when the window is blurred/user is away.

That sounds a bit safer and more predictable — changing the brand new API in lieu of changing the existing API.

The post lock is also currently double the autosave interval, which used to be what controlled the post lock extension. Should we decrease heartbeat even further? Or should we increase the expiration further? Or both? A x2 multiplier seems to make sense, but would 100sec and 120sec be okay?

Because we release the lock immediately and have for a few versions now, I don't think a change from 120 to 150 actually affects much, which is good.

[azaozz]

Because we release the lock immediately and have for a few versions now, I don't think a change from 120 to 150 actually affects much, which is good.

Was thinking the same. We need the difference between the heartbeat blurred interval and lock expiration to be sufficient for slow connections. 30 or even 20 sec. seems safe enough considering that this is the sum of both user A and user B's connection time.

[markjaquith]

Fine with this.

[nacin]

In 24908:

Heartbeat: Reduce the heartbeat from 120 sec to 100 sec when the window doesn't have the focus, to be shorter than the post lock expiration window.

props azaozz.
fixes #24894.

[nacin]

In 24909:

Heartbeat: Reduce the heartbeat from 120 sec to 100 sec when the window doesn't have the focus, to be shorter than the post lock expiration window.

Merges [24908] to the 3.6 branch.

props azaozz.
fixes #24894.