Viewing profile — maxhou

implementation of continue from one luajit fork: https://github.com/zewt/LuaJIT/commit/c0e38bacba15d0259c3b77...

Yes they do. A read() syscall takes longer than a getpid() syscall because read() has more work to do, it actually does a data copy of len bytes, which takes some time (and will be…

How do you know that the dataset fits in L2 ? Assuming pv uses splice(), there is one only copy in the workload: copy_from_user() from fixed source buffer to some kernel allocated …

yes and pv processes are not scheduled on the same CPU core, so different L2 cache.

Does the protocol implement any kind of negotiation (ciphers, ...) ? if not, how would you handle future type of attacks against the then hardwired constructions ? I fully agreed t…

> what ORM to use (or not to use an ORM) do you have something to recommend ? used Rose::DB in the past, then I discovered SQLAlchemy and it's difficult to look back...

http://www.open-std.org/jtc1/sc22/wg14/www/docs/dr_260.htm

> Suppose, for example, that you go to the Bank of America site to transfer some funds or pay a bill. As with Google, and as would happen with any other secure site, it turns out t…

It won't help. To serve its purpose, any AQM (active queue management) like fqcodel must be done at the congestion point. The end-user computer has a faster link than its internet …

from the article: > Each core needs to generate a few thousand data packets per second, because Ethernet packets typically contain up to 1500 bytes. This gives the CPU around 100 m…

You forgot the cost of memory access. The L3 layer checksum is useless because IP packet is small and the kernel has to read/write all the fields anyway. The L4 checksum covers TCP…

simple checksum computation and/or verification, indeed most cards can do (sometimes with restrictions: not for IPv6, not for VLAN...) the other kind of offloading that the kernel …

I'd have expected a small easteregg for the word "bro" ;)

The most obvious is that they have multiple cores, and it's easy to completely disable a non functional one. Now can Intel be more granular than the core level, like running a core…

> And if one atom is in the wrong place, you have to throw away the chip this is certainly the case for CPU but DRAM & NAND ? this is the typical case of designs where you can add …

if you use mmap(), there is virtualy no difference between the streaming/non streaming parsing code.

In the real world, the slow part of "parsing" a CSV file is IO: reading the file content from disk to memory, and from memory to CPU cache. You would avoid reading the file content…

Except parsing all the Android.mk and computing the dependencies is slow as hell. Try running make at the top of an AOSP tree, it takes about 60 seconds, and that part cannot be pa…

OP says the system was swapping. Once your hash table and its linked lists have been swapped to disk, each pointer dereference causes a random disk access, which are orders of magn…

The problem is that all NAT related issues are not because of NAT itself, but because of the required stateful firewalling for NAT. To be able to NAT and un-NAT, you first need to …

Or maybe the opposite ? If you charged Netflix, they would consider investing more money on trying to reduce the bandwidth they use: - innovative video codec - better encoders - ne…

ENOSPC ?

actually since none of its tests ask to sync the data onto the disk, he might just be measuring each method efficiency in creating dirty pages. of course that depends on the amount…

> My theory would be the cost in terms of space and electricity to generate 10Gbe of video streams has dropped orders of magnitude Spot on. You can stream video with basically ngin…

How about asking for net neutrality on DDOS traffic ? I find it unfair that my ISP is shaping it ! :)