Yep, you're right. I corrected myself in another post.
I need to offer you credit; you are right. The issue isn't really PAE, it's how the kernel manages memory on 32 bit x86 architectures with more than 1GB of memory installed. PAE simply exacerbates the problem. Here's an explanation of the complaint:
On ia_32 systems, the kernel splits memory into 3 zones; DMA, NORMAL, and HIGHMEM.
ZONE_DMA is the first 16MB of memory, and is generally avoided unless needed (due to lack of available higher memory, or for DMA mappings.) The kernel tries to reserve this address range for devices that use DMA mapping.
ZONE_NORMAL is an address space that is directly accessible to the kernel, and extends from 16MB to 896MB. Kernel data structures are stored in this space, including the kernel page tables. Memory mappings start to consume a lot of memory in ZONE_NORMAL, and thus PAE on ia_32 with a lot of installed memory can cause out of memory issues, even when there is a lot of available physical memory. User data can be allocated into ZONE_NORMAL, but is preferred to be placed in ZONE_HIGHMEM to free ZONE_NORMAL for kernel data structures.
ZONE_HIGHMEM is memory above the 896MB barrier. This address range is not directly accessible to the kernel. In order for the kernel to access anything in this zone, a temporary map must be made into ZONE_NORMAL. These mappings consume pages of ZONE_NORMAL, and suffer a performance hit. User space processes can access these pages directly (handled by the virtual memory manager system, of course.)
Generally, memory will be allocated to ZONE_HIGHMEM, ZONE_NORMAL, or finally ZONE_DMA in that order of preference.
The x86_64 architecture eliminates the need ZONE_HIGHMEM. ZONE_NORMAL extends all the way from 16MB to the end of physical memory. This approach simplifies memory management, improves performance, and is generally more flexible.
You're correct that there was a major issue with my original post... My memory of the kernel architecture had garbled HIGHMEM with PAE, and I was thinking that PAE required mapping pages above 4GB into lower memory. This would of course cause a huge performance penalty for any process consuming memory above 4GB. I deserve downmods for the technical inaccuracy.
Here's a very brief summary of the problems with HIGHMEM:
Here's a bunch of links used to refresh my memory:
Yes, this is a bit of an oversight on my part. I really should have been discussing the way PAE is implemented on ia32 processors. I had a little bit of difficulty finding information about it online, I'll have to consult my architecture books at home, and will expand on the original post. Here's a bit of the info I could find about PAE weirdness on IA32.
The key quote:
PAE allows a processor to address up to 64GiB in theory but, in practice, processes in Linux still cannot access that much RAM as the virtual address space is still only 4GiB. This has led to some disappointment from users who have tried to malloc() all their RAM with one process.
Secondly, PAE does not allow the kernel itself to have this much RAM available. The struct page used to describe each page frame still requires 44 bytes and this uses kernel virtual address space in ZONE_NORMAL. That means that to describe 1GiB of memory, approximately 11MiB of kernel memory is required. Thus, with 16GiB, 176MiB of memory is consumed, putting significant pressure on ZONE_NORMAL. This does not sound too bad until other structures are taken into account which use ZONE_NORMAL. Even very small structures such as Page Table Entries (PTEs) require about 16MiB in the worst case. This makes 16GiB about the practical limit for available physical memory Linux on an x86. If more memory needs to be accessed, the advice given is simple and straightforward, buy a 64 bit machine.
I don't think you actually read what I wrote.
Also, season 5+ seemed to have a lot of everyone sleeping with everyone else. Amy and Bender, for example? Zap and Leela hooking up, Again?
Both of them are my posts. I meant Flanderization. I guess my writing just sucked today.
I think if you understand how truly horrifying PAE is, you would have no doubt at all that 64 bit platforms were the way to go. There's a lot of memory management cruft in the Linux kernel that x86_64 eliminates.
x86_64 also slipped in a few much needed enhancements to the ia32 architecture, including some extra general purpose registers.
In Fact, TVTropes has an entire section of Flanderization dedicated to Futurama.
(Sorry in advance for your lost productivity.)
I'll never forgive that movie for retconning Seymour.
I don't really think the newer seasons developed the characters... I think they tended to continue the Federalization that had started to set in through season 4 of the original run.
IMO, establishing facts about a character, revealing the back-story of a character, or establishing a relationship between characters is not the same as character development... This is something that the later writers need to understand.
Here's an example of strong character development:
In parasites lost, Fry becomes something of an ideal man thanks to the efforts of a worm he picks up from a truck-stop egg salad sandwich. His strength, intelligence, and artistic ability make him attractive to Lela. For one of the first times in the Series, Fry and Leela become close romantically. But ultimately, Fry gives up all of his new-found strength, because Fry wanted the relationship to be based on who he was in and of himself, rather than how he was perceived by Leela. Fry's character is further developed when he starts to practice the Holophoner in order to become the person Leela respected.
This episode was a huge character defining moment for Fry. This episode did not have a significant impact on Futurama continuity. What it did was to truly help us understand fry as a person in a way that Lars never really could. It developed Fry in a way that his season 5 & 6 relationship with Leela didn't.
I think Fry somewhat devolved as a character during the comedy central run of Futurama. His sincerity is still there, but it seems like a part of his core personality. His stupidity becomes a much more predominant characteristic. He started to feel like a young, orange haired Homer Simpson.
For what it's worth, I think The Late Phillip J. Fry and the Prisoner of Benda were gems from the later seasons. There was some good stuff in seasons 5 & 6, and some bad stuff in Seasons 1-4, but on average I was kind of disappointed by seasons 5&6. I haven't been following Futurama nearly as closely as I once did.
"In the year twenty-five twenty-five twenty-five
The backwards time machine still won't have arrived
In all the world, there's only one technology
A rusty sword for practicing proctology"
I am currently a T-mobile customer, and had a chance to look over the plans. Very excited by this new approach, and hope other providers follow suit.
It's important to note however that tethering (Smartphone Mobile HotSpot, or SMH) is not unlimited, even with the unlimited data plans. The unlimited data plan included 500MB of tethered data, and you can buy more (apparently for $10 per 2GB, but not confirmed.) If you're primarily interested in tethered data, it might make sense to buy the 2.5GB plan, which costs $10 less, and includes 2.5GB of tethered data.
Unfortunately, it looks like T-mobile may be eliminating some of it's other low cost plans with this move. My current plan is $30/mo for more 1500 talk/text minutes, and 30MB of data. 30MB is enough to check a map when I need it, and I can use wifi for my typical data use.
If you have concerns about T-Mobile's coverage, you can supplement it by purchasing an inexpensive daily use phone from Verizon. Pay $2/day when you're traveling outside a T-Mobile coverage zone.
That's fine. The purpose of programs at that level shouldn't be to produce a class full of programmers, but instead to help point students with the aptitude to program towards it as a possible career path.
I'm in the IT field because of a 3 hour computer repair class I took as a kid. I never expected to enjoy it or be good at it - it's just something I did. Turned out to be the right decision for me.
The most recent studies indicate that raising the minimum wage has a negligible impact on unemployment, and that when employment is affected, the net result of the increase in wages is greater than the loss of jobs. Read the wikipedia article as a starting point.
I'm done talking to you.
I think you're more interested in having your straw-man question answered than you are actually discussing wage policy.
If raising the prices of imports reduces imports, and raising the prices of sinful products reduces the sale of sinful products, then why does not raising the price of unskilled labor also reduce the sale of unskilled labor?
Your question is overly simplistic, but I'll take a stab at it.
Understand that each of the actions you mentions have cost and benefits that much be balanced against one another.
Tariff's: Reduce imports, and increase demand for domestic products. They increase tax revenue for the government. They increase domestic employment. They reduce foreign employment. They may reduce quality of life for foreign workers due to decreased employment, or increase quality of life by penalizing unethical employment practices. They may cause retaliatory tariffs which may harm domestic employment more than our tariff's benefit domestic employment.
Sin tax: Decrease demand for sinful products. They increase tax revenue. They may reduce health-care costs (but can increase social security costs due to longer life.) They can reduce crime in some cases (e.g. fewer DUIs) but can create a black-market for un-taxed products.
Minimum wage: Provides increased wages for workers. May cause layoffs due to budget pressure. Will tend to increase spending from low-income earners. Increased spending may result in increased product demand. Increased demand will tend to result in additional hiring. Can cause inflation.
I'm sure there are many benefits and drawbacks not addressed here.
The short version, is that almost any policy you can make will have a wide range of positive and negative effects. The individual effects of a policy do not typically scale linearly with the policy or with teach other. An ideal policy is one that balances costs against benefits. This is similar to the way a demand curve works, but has to take into account many more factors.
Unlike Tariffs and Sin Taxes, increasing wages may result in increased employment due to increased consumption by the consumer class.
Another consideration: a tariff will probably increase demand for domestic products if applied in moderation, but can destroy demand for domestic exports if abused. Likewise, a small minimum wage hike would likely have benefits for our economy, but would result in crushing unemployment if pushed to ridiculous levels, as you suggest in your original post.
To take the opposite approach: If we reduced the minimum wage to 0, would the net effect on the economy be positive or negative?
As I mentioned above, an efficient company hires no more people than are necessary to get the job done. Such a company would be forced to eat increased salary costs out of operating revenue, and would cut jobs only if the increased employment costs made the labor performed unprofitable. However, as we've established, in reality business is neither perfectly efficient, nor terribly rational.
To really understand the impact of increasing the minimum wage, we'd need to look at who is employing minimum wage workers, and the margins of minimum wage employing businesses. If profit margins are high, there's no reason to expect that increasing the minimum wage would actually effect employment.
Again, the minimum wage has fallen significantly since the 70s, and there's reason to suggest that the fall of middle and lower class wages in general have been a significant contributor to our declining employment.
Actually, the largest flaw in your argument is that we've been doing exactly what you propose for the past 30 years:
- Tax rates are down
- Minimum wage is down (adjusted for inflation)
- Productivity is up
- Profitability is at all-time highs
- Executive wages are at all time highs
- Employment situation is dire for many.
Face it, you're clamoring for more of the same stuff that's been demonstrably proven not to work. Top tax rates were at 91% in the 60s. Minimum wage was a living wage. Tell me seriously that the economy is better now than it was then.