21,298 reputation
12348
bio website ripple.com
location Oakland, CA
age 44
visits member for 3 years
seen 1 hour ago

I am Chief Cryptographer at Ripple Labs and one of the architects of the Ripple payment system.


Jun
21
comment How am I able to assign an IP to a bridge interface
Or you can think of a bridge like a switch, and the machine with the bridge has an interface connected to that switch too.
Jun
21
comment linux tc htb bandwidth ceil being ignored and giving improper results
Do you have an IMQ? Otherwise, this won't work. "With linux only egress shaping is possible (except for the ingress queue which can only do rate limiting). IMQ enables you to use egress qdiscs for real ingress shaping."
Jun
19
comment CentOS only detecting 50% of ram on IBM Server
What does the BIOS show? What does memtest86+ show?
Jun
18
comment What is a T1 in modern terms?
I still have a T1 to my home in Murphys, California. It's out of DSL range, so that leaves as the only other options, satellite or dial up. (Comcast says it would cost about $5,000 to run a line to me because local regulations require it to be buried and there's a highway in the way.) Satellite has lousy upload speed and atrocious latency. A t1 is way better than dial up.
Jun
18
comment Route public subnet to client location
What the challenge with doing it with OpenVPN? That's a pretty basic VPN task.
Jun
18
comment Network latency caused by incorrect cable?
If it's a brand new crossover cable that was intended to be used with a gigabit device, it's unlikely to be the problem. (Though I can't understand why anything would ship with such a cable. Modern devices universally have auto-MDI/X and don't need it.)
Jun
18
comment CentOS - binary won't run unless typed with absolute path
You can use strace to see what the program is doing or looking for.
Jun
18
comment Network latency caused by incorrect cable?
Let's say it's wired correctly for gigabit, but can't run reliably at gigabit speeds because it's an old cable that's poorly made. I wouldn't rule out the cable. Because crossover cables have been obsolete for a decade or so, it's very likely to be a piece of junk by modern standards.
Jun
18
comment Network latency caused by incorrect cable?
Whether or not they won't work at all depends on the configuration. I think you're right that with a default configuration at both ends, it probably won't work at all (at least on most devices). But I wouldn't assume that the defaults haven't been changed.
Jun
18
comment Network latency caused by incorrect cable?
I don't believe this answer is correct. The vast majority of crossover cables don't work with gigabit Ethernet. I suspect this is because most crossover cables predate gigabit Ethernet and so don't comply with the gigabit crossover standard (which requires all pairs be swapped).
Jun
18
comment Port Forwarding on Cisco Router
That's very strange, because connection refused means that something is refusing the connection.
Jun
18
comment What does “1-gig switch port” mean in co-location terms?
The "500 GB total monthly transfer" suggests that there is no 95th percentile billing policy but that instead the limit is on the total data sent/received per month.
Jun
18
comment What does “1-gig switch port” mean in co-location terms?
@eric2872 Don't use terms like "gb" because they're extremely ambiguous. That could mean 1 billion bits per second, it could mean 2^30 bytes per second, or anything in between.
Jun
18
comment Port Forwarding on Cisco Router
Where did you test from? Did you test from outside your network? Did you confirm that there's a listening socket bound to 192.168.1.20:80 for traffic to be NATted to?
Jun
18
comment Port Forwarding on Cisco Router
You don't really describe the problem very well. What exactly happens? How did you test whether the rule was working and what results did you get? (You may have just tested incorrectly -- for example, by testing from inside your own network when your rule only applies to traffic from the outside.)
Jun
4
comment Mysql crashing, oom-killer, out of memory, tuning issues?
Swapping will not slow things down, that's a myth. There are two kinds of swapping -- required and opportunistic. Required swapping is an alternative to crashing which, as this question shows, slows things down a lot more. Opportunistic swapping (what you're suggesting he reduce by turning swapiness down) is done specifically because it speeds thing up by making more physical memory available for cache. I gave you a +1 though because you are probably right about the key issue -- he needs more swap.
Jun
2
comment Restrict whole system on certain cores except a few process?
You're probably going about this the wrong way. The solution is probably just to give the latency-sensitive threads absolute priority rather than waste cores when there's no latency-sensitive work to be done. Tell us more about what the latency sensitive threads do.
Jun
2
comment if I name an image with a %2F, I cannot access it and when navigating to it, I get a 404
Your question is really vague. When you say "name an image with a %2F", what does that mean? The filename contains a %2F? Or some tool that lets you name images is given such a name? And what is the "it" that doesn't let you access it? Does it give an error when accessing it from the website? What does the URL look like? What does the URL normally look like? You seem to be assuming we know what you normally do so you only have to tell us about the case that doesn't work. But we have no idea how things normally work for you.
May
26
comment Linux cached memory: Over 85% of cached memory and using swap
The idea that swap makes a system slow is entirely false. Your system will use swap only when it is beneficial to do so.
May
25
comment Why drop caches in Linux?
@AaronHall For RAM to provide any benefit, it must be used. It's the RAM your system is using that is improving its performance.