http://mulix.livejournal.com/
| Sunday,
April 5th, 2009 |
| 12:11
am |
miscellany
I want to update this thing more often, but there's so much
going on,
the days filled with action and counter-action, that before I know it
it's past midnight, and I have to wake up at 5 AM for a workout, and
updating the blog is left on the TODO list for yet another day. Like,
today.
So, content?
I've been a manager for a month and change now, managing the
virtualization and systems architecture group at the lab .
It's an interesting challenge (which is why I agreed to do it), often
frustrating, occasionally exhilarating. To my surprise, the part I like
most is dealing with human beings in their myriad forms. To my
non-surprise, the part I like least is the bureaucracy, but I figured
I'd wait a couple more months before I start tilting at wind-mills. I
still write code (well, debug code, mostly) and conduct research, but
it's no longer the most important part of my day.
On the research front, we had two papers accepted to ICAC 2009
(one full paper and one short paper/poster), both in the general area
of treating virtual machines as black boxes and inferring useful things
about them---performance bottlenecks and boot-time--via statistical
analysis of their inputs and outputs. Another paper, on the DMA mapping
problem in direct assignment, was not accepted to USENIX ATC to my
disappointment, and we are now revising it while looking for a new home.
I
am continuing to work out twice a week with a private trainer who is
seriously kicking my butt. It's rare when I don't finish a workout on
the brink of exhaustion, drenched in sweat. I *love* it. Twice a week
is no longer enough---I crave the endorphin rushes and sore
muscles---so I've also re-started going for long walks, and hitting the
punching bag in the back-yard like I really mean it. The kilograms are
coming off, too, an added bonus.
Last but not least, SYSTOR
2009 is coming up next
month, with a great
program combining academic
research and real-world systems. See y'all there!
Current
Music: Midsummer Eve on TV
|
| Wednesday,
January 28th, 2009 |
| 5:50
am |
It's 5:40 AM. I am is sitting in
an empty room full of half-assembled
furniture, waiting for the personal trainer to arrive and whip my ass
into shape.
|
| Tuesday,
December 23rd, 2008 |
| 11:21
pm |
There will be a half-day workshop
at the Technion's EE department on Thursday afternoon on "Technology
Transfer - from Academy to Industry"
which looks mildly interesting. I am on nominally on vacation this week
and flying to Italy that night, but perhaps I'll go anyway. Anyone else
planning to go?
|
| Wednesday,
December 10th, 2008 |
| 11:17
am |
|
| Monday,
November 24th, 2008 |
| 8:34
pm |
new
IOMMU paper available
New online for your perusing pleasure: "Direct
Device Assignment for Untrusted Fully-Virtualized Virtual
Machines", by Ben-Ami Yassour,
Muli Ben-Yehuda and Orit Wasserman,
IBM Research Report H-0263.
This is a short
paper describing and evaluating our work earlier this
year on direct device assignment in KVM, using Intel's VT-d IOMMU. Not
much new here if you've read our other IOMMU papers, but it does make
two contributions. First, it's the best (and only) available
description (IMHO) of KVM's direct device assignment code, and second
it's yet another data point on the relative performance of device
emulation vs. virtual I/O drivers vs. direct device assignment. As
always, comments appreciated. The abstract follows.
The I/O
interfaces between a host platform and a guest virtual machine
take one of three forms: either the hypervisor provides the guest with
emulation of hardware devices, or the hypervisor provides virtual I/O
drivers, or the hypervisor assigns a selected subset of the host's
real I/O devices directly to the guest. Each method has advantages and
disadvantages, but letting VMs access devices directly has a number of
particularly interesting benefits, such as not requiring any guest VM
changes and in theory providing near-native performance.
In an effort to
quantify the benefits of direct device access, we have
implemented direct device assignment for untrusted, fully-virtualized
virtual machines in the Linux/KVM environment using Intel's VT-d
IOMMU. Our implementation required no guest OS changes and---unlike
alternative I/O virtualization approaches---provided near native I/O
performance. In particular, a quantitative comparison of network
performance on a 1GbE network shows that with large-enough messages
direct device access throughput is statistically indistinguishable
from native, albeit with CPU utilization that is slightly higher.
|
| Wednesday,
October 22nd, 2008 |
| 11:52
am |
notes
for Sunday Oct 20 through Tuesday Oct 22nd
This is not serious, I'm supposed to remember what I was
doing three
days ago? I can barely remember what I had for breakfast this morning.
I
started walking again in the mornings. Today I was up before the crack
of dawn for a brisk walk on the sea shore, and when I got back home, I
even had enough energy left for a few rounds with the boxing bag.
Finished reading Haruki Murakami, and now re-reading Living
the Martial Way. It's a funny little
book, so earnest it's hard to take it seriously, but with nuggets of
wisdom nonetheless.
|
| Sunday,
October 19th, 2008 |
| 9:27
am |
|
| 9:24
am |
notes
for Thursday Oct 16 through Saturday Oct 18
Thursday: just another day at work . In the afternoon, went
to meet an
amazing carpenter (US: cabinet maker). Spent three hours going over the
plans in minute detail, making lots of changes, and then he told us how
much it was going to cost. Staggered to Noga's cauldron for a late
dinner.
Friday: BBQ with old friends at Ira's.
Once upon a time it would've been all Linux hacking, all the time, but
now business and what the kids are doing is that much more interesting.
Progress, of a sort.
Saturday: a day of rest and recuperation.
In the evening off to Mika's 1-year old birthday party. I still
remember the sense of accomplishment we felt at Yael's 1-year old
birthday party, that we actually managed to raise her and she is fine.
Resumed reading Haruki Murakmi's What
I Talk About When I Talk About Running.
|
| Thursday,
October 16th, 2008 |
| 11:36
am |
notes
for Wednesday Oct 15
A day of odds and ends. The WIOV
schedule should be going up today or tomorrow. Continued looking into
the feasibility of a new project which will require coordination with
an inordinate amount of people. Worked on a bunch of new patent
disclosures. Hacked a bit on a new idea for IOTLB design until the
serial port server stopped giving me love, and then went into paper reading mode.
|
| Wednesday,
October 15th, 2008 |
| 11:11
am |
|
| 11:04
am |
notes
for Tuesday Oct 14
Lunch with the Tel-Aviv, business oriented, brunch of the
family in
their nice new house. In the evening didn't feel like doing much of
anything; ended up de-cluttering my publications page.
|
| Tuesday,
October 14th, 2008 |
| 9:45
am |
notes
for Monday Oct 13
More work on the nap and vnic papers in the morning, making
progress
toward their respective deadlines. In the evening BBQ---fillet mignon
and a good wine---with my folks in our garden.
|
| Sunday,
October 12th, 2008 |
| 9:41
pm |
notes
for Sunday Oct 12
Woke up bleary eyed, but settled into a productive day at the
office
debugging by proxy and reviewing a couple of draft papers (vnic and
nap). In the evening got some work done on the secret project, too.
|
| 1:38
pm |
|
| 8:51
am |
notes
for Satuday Oct 11th
Planned, prepared for and executed Yael's 2-year birthday.
Splendid
success, including several tipsy family members. Pictures to come.
Cleaned up afterwards and eventually crashed. Woke back up at 2:30 AM
and tried to convince Yael to go back to sleep until 4 AM. Re-crashed.
|
|
