tag:blogger.com,1999:blog-2987385736576623269.post83073747124335505..comments2022-12-03T18:17:31.695-06:00Comments on Retooling the Datacenter: The Empire Strikes BackUrbanhttp://www.blogger.com/profile/06019262251107123583noreply@blogger.comBlogger2125tag:blogger.com,1999:blog-2987385736576623269.post-76951066292818677902011-04-09T10:49:20.443-05:002011-04-09T10:49:20.443-05:00Jeramiah,
Thanks for the comment. There are diffe...Jeramiah,<br /><br />Thanks for the comment. There are differences between the architectures of FAST Cache and FlashCache, as there are differences on how reads and writes flow through each system's firmware. I thought I stressed that FAST Cache works with both reads and writes. FlashCache doesn't, but I'm not going into a detailed explanation of how WAFL works. Conceptually they're the same -- an extension of cache. Technically there are many differences.<br /><br />FlashCache needs to warm up, it isn't persistent across reboots, it doesn't cover writes. FAST Cache doesn't need to warm up because it is persistent across reboots (except the very first time), it does handle writes. FlashCache is on the PCI bus is has very very low latency. FAST Cache is on SSD and has SCSI and SAS protocol overhead as well as RAID-1 mirroring.<br /><br />There are differences, but they're both an extension of cache. That was the takeaway.<br /><br />Thanks for your comment. I appreciate it and will check out your blog.<br /><br />UrbanUrbanhttps://www.blogger.com/profile/06019262251107123583noreply@blogger.comtag:blogger.com,1999:blog-2987385736576623269.post-62715761703302630082011-04-08T10:31:59.277-05:002011-04-08T10:31:59.277-05:00Urban,
(Disclaimer, I work for VCE on the SP and ...Urban,<br /><br />(Disclaimer, I work for VCE on the SP and Vertical Solutions team)<br /><br />It's good to see the external validation both of the technical side of the VNX/VNXe product launch as well as of the way it was rolled out. It was definitely designed to make an impact on the market! Stay tuned for more on how it plays with the Vblock line as there's some goodness coming there as well.<br /><br />One small comment I'd make is your comparison of FAST Cache to FlashCache from NetApp. PAMII uses a DRAM-on-PCIe model that provides for read-cache only. EMC FAST Cache uses standard SSD drives to extend the array cache for both reads AND writes. Each implementation has its benefits, but there are enough differences that I wouldn't call them direct analogies of one another. If you need more info let me know, I'm trying not to get too far into the (FUD-infested) weeds on it. :-)<br /><br />Hope this helps, thanks again for your feedback!Anonymousnoreply@blogger.com