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Comment: Re:Won't everything need to be recompiled? (Score 1) 70

AIX is full of "hacks" or "modifications" in the TCP/IP stack to greatly improve the performance on POWER architecture on MP systems. Have any of these made it into mainstream Linux? Are they even valid on Intel architecture?

For instance, when running a benchmark on an AIX POWER system, try increasing the load, and see if your results go up. It can happen, that you increase the load, the CPU utilization climbs, but you benchmark remains the same. Well, you might be hanging in spin locks. AIX supports instrumented locks, so you can check this with the lockstat command.

Another potential problem is that two many global variables are located in the same CPU cache line. So you can pad single variables, so that they are in separate cache lines. Or, even worse, you have one global variable that is being constantly updated by all processors, and is constantly causing cache invalidation on the memory bus. Then you need to do a hardware memory bus trace, with an HP logic analyzer that looks like something out of Hentai Porn. Then you need to write up a patent or something:


So I'm just wondering if all this poop will be done for Linux on OpenPOWER . . .

Comment: Re:Won't everything need to be recompiled? (Score 1) 70

Yeah, but Linux on POWER today runs on Big Endian. See another post in this thread about IBM intentions, but Red Hat has not announced support for Linux on Little Endian yet. That one hurts.

Linux on OpenPOWER doesn't exist yet . . . or does it . . . ?

Comment: Re:Won't everything need to be recompiled? (Score 2) 70

AIX was pretty cool way back when, when they introduced 64-bit support. The processor was 64-bit. However, you could run a 32-bit kernel or a 64-bit kernel. And you could run a 32-bit process or a 64-bit process on either of the kernels.

So what does some poor chump (i.e. me) who is tasked with writing a device driver for AIX need to do? Well, first #ifdef the code, so you compile different stuff, depending on if you are building a 32-bit or 64-bit version of the device driver. Then you needed to add simple "if" statements in the device driver, to check if you were running a process in 32-bit or 64-bit mode. Then according to the mix, you would have to thunk the addresses, when copying the data from user space into kernel space.

Fun stuff. I can't believe that I actually did this in a former life . . .

Comment: Re:Won't everything need to be recompiled? (Score 1) 70

A simple recompile won't do it . . . some programs, like your TCP/IP stack have dependencies on Endianess. IBM's POWER has been traditionally Big Endian. Linux is mostly Little Endian. There are C macros, ntoh() and hton() that do the required byte swapping for you . . . if you remember to use them! I have seen code that would run fine on a Big Endian machine . . . but would fall over and die on a Little Endian machine.

Sorting out all these problems is painful grunt work. Although, at one point, IBM tried to port AIX to Intel64. It was called Monterrey, or something like that. So IBM does have experience in doing this. It's just a question if they will fork out the dollars required to do this. And if the people know how to do this have been laid off.

Comment: Re:N4N? (Score 1) 284

No, but he should be forced to dress like a woman, on odd or even days, depending on whether his birthday is odd or even.

That is my simple and effective cure for sexual diversity in IT. Half the time men will be forced to dress as women, and women be forced to dress like men. Hey, presto, when someone from the government comes to do a headcount, he or she will find an equal number of men and women. Problem solved.

Jesse Jackson can be placated by having a whites wear black face and blacks wear white face policy, as well.

The most fun would be the Native American Indian role: You get to turn your cubicle into a steamy, smoky sweat box, while consuming hallucinogenic Peyote.

Comment: "Ditchin' the pSeries down here, boss" (Score 2) 70

So, is IBM going to ditch making their own POWER pSeries, and totally go for the ARM model of just licensing the technology for OpenPOWER . . . ?

Just like in the PC world, folks stopped buying IBM built PCs, when cheap clones were available. What would be the advantage of buying an IBM built OpenPOWER system, as opposed to a much cheaper Chinese built clone . . . ? Maybe the IBM system will have some kind of "secret sauce" . . . ? Like a MicroChannel (har, har).

At any rate, somebody is going to have to invest a lot of money to make sure that Linux runs well on OpenPOWER, in order for this to succeed.

+ - Ikea Refugee Shelter Entering Production

Submitted by jones_supa
jones_supa (887896) writes "A rather interesting product, Ikea's line of flatpack refugee shelters are going into production, the Swedish furniture maker announced this week. The lightweight Better Shelter was developed under a partnership between the Ikea Foundation and the United Nations High Commissioner for Refugees (UNHCR), and beta tested among refugee families in Ethiopia, Iraq, and Lebanon. Each unit takes about four hours to assemble and is designed to last for three years — far longer than conventional refugee shelters, which typically last about six months. The product is important tool in the prolonged refugee crisis that has unfolded across the Middle East. The war in Syria has spurred nearly 4 million people to leave their homes. The UNHCR has agreed to buy 10,000 of the shelters, and will begin providing them to refugee families this summer."

Comment: Re:N4N? (Score 2) 284

Hell Bill Joy is a senior partner.

. . . and if anyone wants to file an editor gender suit . . . Bill Joy wrote vi . . .

That one would be a hoot and a half in court. None of the jurors would really understand what it was all about, and the court case would be finished, before emacs loaded.

+ - Ellen Pao Loses Silicon Valley Gender Bias Case Against Kleiner Perkins->

Submitted by vivaoporto
vivaoporto (1064484) writes "As reported by the New York Times, USA Today and other publications, a jury of six men and six women rejected current Reddit Inc CEO Ellen Pao’s claims against her former employer, the venture capital firm Kleiner Perkins Caufield & Byers.

Ms. Pao’s suit, that allegged employment discrimination based on gender, workplace retaliation and failure to take reasonable steps to prevent gender discrimination, asked $16 million in compensatory damages plus punitive damages.

The jury decided, after more than two days of deliberation and more than four weeks of testimony, that her formed employer neither discriminated against the former junior partner for her gender, nor fired the complainant because of a high-profile gender discrimination lawsuit against the firm in 2012.

She alleged that Kleiner Perkins had promoted male partners over equally qualified women at the firm, including herself, and then retaliated against her for raising concerns about the firm’s gender dynamics by failing to promote her and finally firing her after seven years at the firm after she filed her 2012 lawsuit."

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"Pay no attention to the man behind the curtain." -- The Wizard Of Oz