bcache on a laptop

Gents,

I'm still trying to get a comfy bcache installation on a laptop. To summarize thus far,

1. I have a Debian system that boots from bcache
2. No version of 3.10 that I have tested (either from the Linux git
or from the bcache-stable branch of the bcache git) will allow the laptop to sleep or hibernate properly.
3. Every version of 3.11 that I have tested results in severe data
corruption. (I wound up having to reinstall my system as a result.) Using 3.11.0 built from the 3.11.y branch at kernel.org, the corruption was subtle at first; eventually programs started segfaulting. Running "sync ; echo 3 > /proc/sys/vm/drop_caches" would resolve the corruption issue (I'm in writethrough mode), but the root was destroyed when corruption occurred in the middle of a nightly upgrade.
4. When corruption isn't an issue (e.g. in a 3.10 kernel), I'm
getting between a 50% and 80% cache hit ratio (again in writethrough, not writeback). I'm pretty happy about that. :)
5. Creating a large number of small files seems to be quite a lot
slower than it was without bcache. (For instance, installing xfce4 and its dependencies into a fresh chroot takes about two hours.) I've noticed that Debian packages in particular take longer; kernel header packages often take close to half an hour by themselves. (Can anyone posit a reason for this?)

I'll be trying the 3.10.12 bcache-stable shortly, though I expect that it won't make a huge difference in the hibernation problem. I just wanted to record this information in case someone else decides to give this a go.

Cheers,

Zach