Hi all,
I was going to invest in a USB 3 flashdrive as L2 cache. Any suggestions for the size. Will 32GB be enough?
Thanks,
Regards
Joseph
USB3 as L2 cache
Re: USB3 as L2 cache
8GB could be enough depending on your usage. I use about 8GB of level 2 cache for my games, and it keeps a consistent >90% hit rate. However, I haven't had good luck at all with USB, even USB3.
Most USB flash drives have much slower write speeds, and their random 4K write can be truly awful (I'm lucky to get 300kB/sec 4k random write). Unfortunately, the cache can't take any more data in until it's flushed some to L2, which means initial loads can be very slow. Even after the persistent L2 cache has been filled, I was seeing slower read times than without cache, even at >80% hit rates. I did my tests with typical consumer-grade USB drives (Sandisk Cruzer, Patriot Supersonic). Load times might be worth it with enthusiast-grade drives such as the Patriot Magnum, but I haven't seen good benchmark numbers for those when it comes to 4K random writes.
Unless you're on a laptop without any other option, I believe the cheapest SSD would still outpace a USB3 drive.
Most USB flash drives have much slower write speeds, and their random 4K write can be truly awful (I'm lucky to get 300kB/sec 4k random write). Unfortunately, the cache can't take any more data in until it's flushed some to L2, which means initial loads can be very slow. Even after the persistent L2 cache has been filled, I was seeing slower read times than without cache, even at >80% hit rates. I did my tests with typical consumer-grade USB drives (Sandisk Cruzer, Patriot Supersonic). Load times might be worth it with enthusiast-grade drives such as the Patriot Magnum, but I haven't seen good benchmark numbers for those when it comes to 4K random writes.
Unless you're on a laptop without any other option, I believe the cheapest SSD would still outpace a USB3 drive.