Tracker offline, apparent reason, and updates

Here's what we know right now:

There appears to be an issue in the SSD raid 10 array that is the main storage for the database.
This is leading to very slow disk access, which in turn causes things to be slow.
When the tracker is enabled, it's far too much disk write for it in this degraded status.

We think we have identified which disk is failing, and are working with the data center to get it replaced, however due to some odd circumstances, this is going to be some number of hours.
The drive we think is failing would need replaced soon anyway, so replacing it is prudent.

I'll keep this updated as things go on.