From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: Date: Wed, 23 Apr 2008 20:24:33 -0500 From: "Eric Van Hensbergen" To: "Fans of the OS Plan 9 from Bell Labs" <9fans@9fans.net> In-Reply-To: <22dab4d01b21fbbb552e41444d65fa6d@quanstro.net> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <22dab4d01b21fbbb552e41444d65fa6d@quanstro.net> Subject: Re: [9fans] new lguest port available Topicbox-Message-UUID: 99488f08-ead3-11e9-9d60-3106f5b1d025 On Wed, Apr 23, 2008 at 7:53 PM, erik quanstrom wrote: > > what i'm saying is boils down to 10ms + 100ns is essentially 10ms. > so it's slower, but at a level a couple (or three) orders of magnitude too > low to be very significant. > ah, but its not always 10ms because of the page cache...but I'm digressing to a new low level. Actually, the argument that Ron and I both made is that they should ditch both the network and the block (and the console) drivers/protocols and just use 9p for all three. It adds your slight 100ns of overhead, but unifies all God's children. However, given that the virtio stuff is infinitely better than the Xen approach and the other craptastic virtualization I/O schemes, we decided to leave well enough alone and do the 9p stuff ourselves (which begs the question why Ron is using the disk and net drivers and not the superior 9p driver, but I digress yet again). > > [...] adding extra layers for nothing. > > avoiding maintaing a second interface doesn't count? and according > to ron, the network is fast right now. this virtual ata interface isn't. > come back to his jebus and remember that the only real goal of all virtualization people is to support windows -- they'll always have a block device. It will get faster, you can hear the millions of monkey's typing in the distance. > > now i'm really dreaming but ... why don't you convince the virtualizer guys > to implement aoe instead of a straight ata interface for high performance. > it would be less work for them too, and would eliminate the extra layer -- > vblade. > I misled you a bit when I said it was AOV, its actually much closer to just the straight block device. No real naming issues and it back-ends into a bunch of stuff they want like copy-on-write and what not. WAIT - I already hear you complaining about my lack of consistency because I was talking about kernel-cut-thru's -- however, the nature of the game is there are several back-ends for several different solutions. I like AOE, I think its a great general solution, but I don't see it solving their problems and it complicates some of their security, failover and migration schemes. Its close to the equivalent of saying why doesn't Linux use AOE as its block driver interface. -eric