mtanski

46 ms·

361.
by mtanski 11y ago
You would also need to align the stack per. target requirements (gcc keyword, or offset the address). The aliment guarantees for char[] placed on stack are probably insufficient for many machines.
362.
by mtanski 11y ago
The code in question strikes me as being a proof of concept. Obviously, a more complete implementation would be more complex. In the real world you'd create a stack with mmap with the MMAP_STACK flag. You would ensure the stack is prop
363.
by mtanski 12y ago
I'm not sure the network stack in userspace is going to help MUCH in this scenario. sendfile() does the disk (fd) read / enqueue to network socket (fd) in the kernel space. This ends up being DMA to pagecache from the file and ho
364.
by mtanski 12y ago
Can anyone point to an alternative to Gandhi.net for domains / SSL? Works well, good service, not godaddy.
365.
by mtanski 12y ago
Up votes by people who don't really buy all the Rust marketing about safety of the language, at least how it's gone about. Personally speaking, and looking others threads on /r/rust, there is a fair amount of frustration
366.
by mtanski 12y ago
Ugh, I really wish the marketing people would pick different name for this evolution of SSD drives then NVMe. At least the NVM part stating: Non-Volatile Memory. The current iteration of what we call NVM is just SSD on PCIe busses so they
367.
by mtanski 12y ago
Except when escape out to unsafe (as a lot of rust code does) or stop using rust because the borrow checker is brain dead: https://github.com/rust-lang/rust/issues/6268 https://github.com/rust
368.
by mtanski 12y ago
Thanks to Brendan it's much easier to sell people on perf. You just link them to Brendan's slides.
369.
by mtanski 12y ago
I've been trying to tell people to use perf for years now. I think there was a lot of disservice done by early versions that were buggy, crash and freeze prone. Still better then I oprofile before it. It only got better once they added
370.
by mtanski 12y ago
cmurf. What the article and John is talking about is CephFS (which we do use). As you can see that is in the heading of the quote that you took. What John is not talking about is the Object Store (S3 compatible) or RBD (rados block device,
371.
by mtanski 12y ago
This is pedantic, but unless the filesystem is build specifically for WORM devices you always end up with some non-sequential data. In the use cases you're describing they'll be some filesystem metadata (freemaps, directory entrie
372.
by mtanski 12y ago
We spent a bit of time talking about about these "shingled drives" at the LSF/MM summit earlier in the week in Boston. Storage is becoming a more fascinating topic with so many technologies (SSDs, shingled disk, non-volatile
373.
by mtanski 12y ago
Tiered storage is already here. If you're using block storage in the cloud those guys are already do all sorts of optimizations (for their costs) that include tiering. And on your own desktop / own server side you can do this toda
374.
by mtanski 12y ago
It's def a step in the right direction. At least in terms of letting you mechanically transform queries. The downside (IMO) is that it's still reflecting SQL the language ... not the relational model.
375.
by mtanski 12y ago
I would like to say lets step back and not conflate SQL and relational databases together. Clearly SQL as the language the primary way most people interact with relational database. In my my mind SQL as a language is a huge PITA. First, par
376.
by mtanski 12y ago
What this approach does is only read the data for you if it's in the kernel page cache. If it's not it's your responsibility to get it somehow (maybe through a regular read call). Today it does not enqueue a any kind read-ahe
377.
by mtanski 12y ago
Yay Postgre and thanks for running the numbers. However, it would be nice to see a summary of the major changes that made a impact on the performance on each version. I like geeking out on db internals.
378.
by mtanski 12y ago
The point is to reduce latency introduced between eventloops and io threadpools. Not every application can use sendfile() due for a number of reasons (post processing, TLS, ...) I'll be talking about this at the LSF MM/FS summit i
379.
Non-blocking buffered file read operations(lwn.net)
40 points by mtanski 12y ago|4 comments
380.
by mtanski 12y ago
I had neighbors who wanted to make sure when the hallway was being painted they only used low VOC paint. They were somewhat offended when I told them the carpet they put uses a bonding agent that will off gas for years or they their childre
381.
by mtanski 12y ago
The amount of products that use formaldehyde somewhere in the process is staggering. From glues used for wood (floors) to fabric softening (carpets, baby clothes), inks, building materials. This is a much bigger deal if you live in a "
382.
by mtanski 12y ago
With great power comes great responsibility. mmap is one of those tools. Keep in mind that your whole linux system essentially mmaps your binaries / shared libraries when you run an application. And with caveats our world still keeps g
383.
by mtanski 12y ago
In test case in the article they are sending the smallest possible ethernet ethernet frame at 84 bytes. Further, the caveat here is that they can do that on a single CPU only in the kernel layer. Once you involve userspace at the same packe
384.
by mtanski 12y ago
A couple points about RedHat: First, it develops almost everything out in the open. That includes developers communicating with their coworkers through public mailing lists for those projects. Sometimes those are hosted by Redhat but most o
385.
by mtanski 12y ago
I don't know if the AUFS overhead matters in many workloads. If you're using for deploying code that gets loaded once and you're and you're not performing a lot of filesystem access. Think of many webapps, their assets a
386.
by mtanski 12y ago
Hence my last point at states being better able to deal with issues in a more localized matter.
387.
by mtanski 12y ago
I think you're right, the headcount reduction number would most likely be conservative. But what I can imagine is that the overhead of administering multiple programs (some overlapping) is larger then just the salary and benefits costs
388.
by mtanski 12y ago
I've come around to generally agree with the basic income guarantee. Both in premise of the problem and how it tackles the. What I don't believe is that the problem is tenable in the United States. At least, I can't see it ha
389.
by mtanski 12y ago
If I remember correctly from a high scalability post about WhatsApp it was also on bare metal. So more complexity to manage then a simple AWS setup where you can tear up/down in seconds.
390.
by mtanski 12y ago
Storing a lot of "colder" data but where you might want to be able to have better then S3 speed of transfer.

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