grahamperrin wrote:8 GB Kinsgston DataTraveler 400
I don't know whether people should laugh or cry at this choice of hardware for L2ARC.
Quantitatively, for maybe a day or two I experimented with secondarycache=metadata. Nothing conclusive, but output from zpool iostat suggested that not much of the 8 GB would be used in my cases (restarting the Mac more often than an average user). I could have experimented with longer warm-up periods but I decided to revert to secondarycache=all.
Qualitatively, over the past two months or so, it does
sometimes feel that overall performance benefits – just a little – from attachment of this device to the MacBookPro5,2. For example: new tabs in Safari whilst the Mac was extraordinarily busy with other things – I had a sense that with the thumb drive, there'd be a little less waiting time in response to Command-T.
Using an ordinary thumb drive in this way is
not something I'd recommend. I'm toying, rarely paying attention to stats …
PostscriptOne of the reasons for me not bothering to benchmark or measure, in recent weeks, has been my use of pre-release builds of the OS.