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The Bike Shed


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Originally published in Queue vol. 8, no. 6
see this item in the ACM Digital Library



Richard L. Sites - Benchmarking "Hello, World!"

Noor Mubeen - Workload Frequency Scaling Law - Derivation and Verification
Workload scalability has a cascade relation via the scale factor.

Theo Schlossnagle - Monitoring in a DevOps World
Perfect should never be the enemy of better.

Ulan Degenbaev, Jochen Eisinger, Manfred Ernst, Ross McIlroy, Hannes Payer - Idle-Time Garbage-Collection Scheduling
Taking advantage of idleness to reduce dropped frames and memory consumption


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Displaying 10 most recent comments. Read the full list here

Loki Verloren | Wed, 25 Apr 2018 10:30:09 UTC

I really really enjoyed reading this article and I am in the process of attempting to implement a binary search tree based on a similar model, and in particular the remapping between the array store and the tree structure answered a question that I intuitively grasped but didn't have an image in my mind about how this problem of causing a page fault with every row below the first 4kb of the tree. I don't 100% get how the mapping translates to my intended application of a left-right sorted tree, exactly, but I will come up with it a lot more easily now I have seen this.

My whole direction in my current project was all about finding a way to exploit the far greater speed and far lower latency of CPU caches, and this is exactly demonstrating that my line of inquiry was correct.

Neel | Sun, 18 Mar 2018 06:51:31 UTC

skipped bath and reading this. This is intresting

BlueRaja | Thu, 21 Apr 2016 21:20:30 UTC

So you reinvented the T-tree, plus some Straw Man graphs and some comments on how you're smarter than the entire CS field. Congrats?

Steve | Tue, 11 Aug 2015 03:39:02 UTC

Google "cache oblivious algorithms" for good theoretical treatment.

zeroday1 | Mon, 22 Dec 2014 21:32:45 UTC

I often encounter the following error on a consistent basis upon visiting the famous shop network HSN.


Error 503 Service Unavailable

Service Unavailable Guru Meditation:

XID: 1376938831

Varnish cache server


There really is no reason to suspect that my experience encountering this error is related to a problem on my system because I do not maintain any conflicting configurations on my pc. No matter what browser I use, I still get this error. I've visited their site before with no problem, however it almost seems like now it is a regular occurrence to come across this error.

I have ample reason to believe this has to do with a problem on their website, specifically with regard to website maintenance, or lack there of...

Try telling HSN that, and you might just get a variety of responses depending upon whom you speak with, but you can rest assure that no matter whom it is at HSN, they're all experts...(Pun intended of course)...

A. Bit Miffed | Sun, 14 Sep 2014 23:15:38 UTC

It's rare to see this kind of hubris in a computer publication. But, oh well. When quantum computers become the norm, we'll see an article that Poul-Henning Kamp was doing it wrong.

asd | Tue, 22 May 2012 04:53:47 UTC

buy more ram bros

iitg | Mon, 12 Dec 2011 09:44:22 UTC

I think some said "buy more ram" in the comment above, that wont be of much help as we are talking about an algorithm which minimises disk access as well as cache miss! Nice article.

Dutch Uncle | Thu, 30 Jun 2011 16:02:25 UTC

Lots of people have been paying attention to memory hierarchy for a long time. I worked for SyncSort on IBM mainframe data sorting and manipulation utilities. I can assure you that every single execution of the SyncSort utility started with an analysis pass that included comparing the effective size of data key indices to the available cache reported by the processor, as well as comparing the available RAM to the total data set size, in order to tune the operation into the best number of iterations of the best sized chunks of data. In the universe, things do happen outside of one's personal knowledge.

Sepp | Fri, 25 Mar 2011 13:34:37 UTC

An interesting comparison of Varnish, Apache Traffic Server (another proxy cache) and G-WAN (an application server with C scripts):

Apache Traffic Server is an HTTP proxy and cache server created by Inktomi, and distributed as a commercial product before Inktomi was acquired by Yahoo.

Yahoo says that it uses TS in to serve more than 30 Billion objects per day. They also say that TS is a "product of literally hundreds of developer-years".

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