new connexions collection available
I have been working on my Connexions submissions again recently, and have a collection ready for use (it will be growing as time goes on): “Debugging and Supporting Software Systems”
I realize there are some small typos in the current text, but I will be addressing that in a upcoming revision 
I’d love to get feedback from anyone on how it could be improved/expanded.
Topics: education, news, personal, technical, update | No Comments »
lightsquared attacking gps manufacturers
The LightSquared situation keeps getting more interesting. InfoWorld has another story on them attacking GPS manufacturers for not being more careful about filtering adjacent frequency bands (per a DoD recommendation from 2008).
LightSquared is at loggerheads with makers and users of GPS (Global Positioning System) over interference between the navigation system and its planned cellular LTE (Long-Term Evolution) network. That network would transmit on frequencies close to those used for GPS. The company has long argued that makers of GPS equipment are to blame for the interference because they don’t use strong enough filters to keep their receivers from searching for signals in LightSquared’s bands. But this is the first time LightSquared has accused the vendors of flouting a specific rule.
The DoD’s GPS Standard Positioning Service Performance Standard called for GPS receivers to filter out transmissions on frequencies adjacent to the GPS band, LightSquared told the FCC in a filing related to the agency’s ongoing consideration of the company’s network proposal. The standard, issued in September 2008, recommends that receivers reject all transmissions on frequencies that are more than 4MHz outside the GPS band, said Jeffrey Carlisle, LightSquared’s executive vice president for regulatory affairs and public policy. That 4MHz buffer is essentially a “guard band” to protect operations on either side, he said.
LightSquared plans eventually to use frequencies adjacent to the GPS band for its LTE network, but after mandatory tests earlier this year showed strong interference in that area, the company said it would start out in a slightly lower-frequency block.
Here’s something that’s a little disturbing, though:
There is no mandatory standard for filtering in GPS receivers, and the FCC does not certify the devices for this
And here:
In addition to the DoD recommendation, the International Telecommunication Union, a United Nations agency, has also warned since 2000 that stronger filtering might be necessary to protect GPS from nearby transmissions
The ‘Coalition to Save Our GPS’ had the following to say:
“GPS receivers incorporate filters that reject transmissions in adjacent bands that are hundreds of millions of times more powerful than those of GPS. What LightSquared is proposing, however, is to transmit signals that are at least one billion times more powerful,” the group said in a statement. “There has never been, nor will there ever be, a filter that can block out signals in an immediately adjacent frequency band that are so much more powerful, nor has LightSquared put forward any credible, independent expert opinion or other evidence that this is possible.”
I’m no expert, but “hundreds of millions” is distinctly not far-off from “one billion” (since one billion is equal to ten hundred million). I also acknowledge not having much domain expertise in radio signals, transmission, etc – but what LightSquared is looking to do seems a lot more useful than worrying about some poorly-built GPS receivers.
The FCC said earlier this week that it would not allow the LTE service to launch unless the interference issue was resolved.
LightSquared has said it is confident the plan will be approved next month.
Topics: news, technical, update | No Comments »
light shows
I’ve recently had some travel for work that had put me up in Indianapolis.
Tuesday evening I watched the best light show ever: a miles-high, miles-wide thunderhead flashing nearly constantly for over 30 minutes.
It was a little east of where I was staying in Fishers, but man was it pretty!
For the record, God’s fireworks are cooler than any 4th of July party 
Topics: fun, personal | No Comments »
connexions
A few years ago I was working for Sigma Xi as an intern, and was introduced to the then-young Connexions project from Rice University.
This week I was reminded of the service, and have started looking into ways I can contribute to their open repository of educational materials.
I’d written two articles published there when I was at Sigma XI, and while one of them now looks somewhat quaint and dated, I think there are some other areas that I could contribute to that would be helpful.
CNX is free and open to anyone to use, add-to, modify, and reference – so have fun
Topics: education, fun | 1 Comment »
the fcc decides to intervene on lightsquared
I’ve taken an interest in LightSquared recently.
Today InfoWorld reports that the FCC “won’t allow LightSquared’s proposed mobile broadband service to interfere with GPS signals, even though the potential interference would be caused by GPS receivers picking up signals outside of their designated spectrum”.
So, the devices are in error, but the FCC is going to prevent LightSquared from interfering?
Sounds like the FCC should be going after the receiver manufacturers to ensure their systems don’t bleed over, rather than after a company not operating on GPS spectrum.
Wait, I forgot: that’d be too logical for a government agency 
Topics: news, technical, update | 2 Comments »
why technical intricacies matter
I have been working on a upgrade for one of our customers for nearly a month.
Last week we spent about two hours focused on one specific problem that had been rearing its ugly head on an exceedingly-frequent basis: one of the components of the application was routinely pitching OutOfMemory errors from the Java Virtual Machine (jvm). The errors were actually being returned from WebLogic (currently an Oracle product; previously from BEA).
Much googling of the error messages returned the following Sun bug:
http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=4697804, and the workaround:
“Disable VM heap resizing by setting -mx and -ms to the same value.“
This will prevent us from hitting the most common sources of the vm_exit_out_of_memory exits.
The best thing to do is increase swap size on the machines encountering this error.
[If you want to skip the rest of this, feel free: the short version is we boosted swap space from 1GB to 13GB, and it works like a champ now.]
Important Things You Should Know™
- The version (1.4) and platform (32-bit) of Java is used for a variety of reasons by this product in this component
- A 32-bit OS/machine1 can only access ~3GB of RAM (due to OS overhead and bus address mapping strategies)
- A 64-bit OS/machine can access between 248 and 264 bytes (256TB-16EB) of memory (depending on addressing model used)
- There are two types of memory a system can use: heap and stack
- The jvm gets memory for itself from the host OS from the heap
- If more memory is need by the Java application in question, and it has not yet exceeded the max (
-Xmxargument) amount available to the jvm, the jvm will get more memory for itself from the system - The 32-bit jvm has a certain amount of overhead itself (I have seen 5-25%, depending on the application)
Environmental issues for the application in question
- 8 CPUs
- 32GB physical memory
- ~9GB RAM in use, the rest unused
- RHEL 4 64-bit
- 1GB swap
Go check out this video while you think for a few seconds
Oh, you’re back? Welcome!
More details about the Sun jvm: when the jvm needs more memory, so long as the system can issue it, it will ask for a multiple of what it really needs (observationally about 40%, or 1.4x the “actual” request). And while it is asking for more memory, it swaps itself out to swap space (virtual memory, or a special location/partition on the drive). After it gets its new allocation, it loads itself back in from swap, and goes on its merry way.
Why does it ask for more than what the application ”actually” requested? It’s a best-guess on the part of the jvm – if you have allocated 256M of RAM minimum, and 1G max, when the application asks for 257M, the jvm doesn’t want to ask for more RAM too often from the OS, so it asks for ~360M, with the theory being that if you needed 1M over your initial amount, you will likely need yet more. This continues on until the jvm has asked for as much RAM as it is allowed, or until the application quits – whichever comes first.
Last piece of useful technical data:
- The specific component in the application I was working with asks for 256MB to start, with a cap of 1280MB (we raised that to 2560MB (2.5GB) as an initial attempt to stave-off OutOfMemory errors)
I know it’s been a little while, but think back to that initial list of Important Things … and add into the mix that the component in question was chewing an entire CPU (in normal operation it rarely will go above 25%), and was using 3600MB of virtual memory and 2.8GB of real RAM. That’s a problem. First, because we have 32GB of real memory – there’s no reason the whole component (2.8GB is equal to our 2.5GB max plus some jvm overhead). Second, because while it’s chewing an entire CPU, it’s never actually coming up, or, if it does, it’s taking an hour or more (when normally the entire application will start in 12-20 minutes from power on).
What was the problem with this ONE component? The detail is in the list of environmental factors: there was only 1GB of swap space. Uh oh. That means that unless the jvm asks for all 2.5GB up front, it will have to keep re-allocating memory to itself from the system. But with only 1GB of swap space, it has no place to unload itself to while it asks for more and then load itself back into RAM.
What to do? Let’s go back to that obscure Sun bug: “increase swap size on the machine”. We tried going from 1GB to 13GB (had a 12GB partition not being used, so we flipped it to be a swap partition) and rebooting the server.
After increasing swap space, not only does the application start in about the expected amount of time (~15 minutes), but it never pegs the CPU! Woot!
With a newer version of the product, there is an installation prerequisite check to ensure that there is as much swap space as physical RAM installed – but no explanation of why this is now the case.
Whether the above travails are the entire reason, or merely a single example of why it’s important, I won’t be installing onto any machine that doesn’t have enough swap again.
1 without special drivers/kernel modifications
Topics: insights, technical, warning, work | 2 Comments »
auctions
Following-on with what my wife wrote last week, we’ve been enjoying going to local auction houses again recently – even on nights when there’s nothing we want, it’s still at the very least entertaining
The last couple times we’ve gone, we’ve been to the Williamsburg Auction Center, near where my wife grew up. The building is clean (no smoking indoors, or near the doors), the organizers are professional and fun, and there is food available for purchase (“Supper will be available at Judy’s AUCTION HOUSE RESTAURANT Serving 4:30 p.m. to end of auction. Menu includes Judy’s homestyle Southern Recipies and Delicious Desserts!”).
So far we’ve found some interesting old books, and a few other odds and ends. If you can find one near you, I’d encourage you to go – for the entertainment value, if nothing more
Topics: fun | No Comments »
staybridge replies – the next week
In follow-up to my post from last week, two members of the Staybridge staff contacted me on Wednesday of this week. Their replies are posted below. Also, a disclaimer: I never asked for anything to be done in recompense for the situation – I just wanted it fixed.
Mr. Myers:
Please accept my apology for the delay in responding to your email. I have received it through IHG Guest relations and was not aware of it until this morning. I have copied the email to go over with the executive housekeeper. While we have been challenged with very large sports groups, staying one week or longer, it is no excuse for poor service. I was not aware that the complimentary room was not a direct benefit to you. In lieu of the issues you encountered I will add 10,000 priority club points to your account. The description of your stay, by no means, represents the type of service we strive to present to all guests. Thank you for taking the time to let me know. If I may be of any further service please do not hesitate to contact me directly my cell phone number is 317-640-2708.
Sincerely
Gary W MillerGeneral Manager
Staybridge Suites
Indianapolis/ Fishers
317-577-9500
And from the other manager (quoted as sent, including any typos):
Hi Warren,
I was reading over your comments in regards to your recent stay with us. I want to sincerely apologize for the problems that you encountered. I understand that the company was paying for your stay and that the comp night was not an actual benefit to you. I have included a free night certificate for you to use in the future. While it doesn’t make up for the problems you had, I hope that you and your family can use it for personal use next time you are in the area. I have also upgraded the room type to a one bedroom suite for you. I will be sure to address these items with housekeeping and the front desk, so that the same mistakes doe not incur. Again, please accept my sincerest apologies.
Natalie Page
Guest Services Manager
Staybridge Suites Fishers-Indianapolis
317-712-5101 direct dial
317-577-9500 front desk
317-712-5200 fax
When I emailed Gary this morning asking why he had not replied to the emails I sent him directly, this was his reply:
Mr. Meyers
That is the correct email address. However, I am having issues with my email account over the last few weeks. I am receiving an exceptional amount of “spam”. It is not unusual for me to have over 150 emails every morning. Yours may have been deleted by mistake. I did however receive your email through IHG Guest Relations. That is what I was responding to. I hope we can be of service to you in the future.
Sincerely
Gary W. Miller
Yeah, I get a lot of “spam”, too – but when the subject line includes not only the reservation, but my Priority Club number, and is addressed directly to you from a corporate address… it sounds like a weak response.
Regardless, at least there was some form of reply to the situation – not what I would have expected, but I suppose it’ll do.
Topics: complaint, travel, update | No Comments »
personal vs professional blogging
A friend of mine recently pointed me at the newspaper-associated blog of a “recent Appalachian State University graduate and now a freelance reporter for The Charlotte Observer”.
Ms Penland seems like a nice person – but her writing is not at all what I would expect for a blog associated with a newspaper – it is far more like a personal journal of a teenager than a professional blog of a reporter.
I’m all for personal voice showing-up in folks’ writing (it certainly does on all of the blogs I follow – and on the ones I write 
) – but when you’re writing reviews for a newspaper, it would seem like you’d try to be a bit more … professional in your writing.
Besides the myriad grammar errors (I know – we all have them, but certainly some proofreading should be done to catch things like “was is“), it seems she has a routine dislike for “chains” – and yet visits many. She also refers to her boyfriend in many of her reviews: a perfectly fine thing to do in passing, but she ends up making some of them more about him than about the place they went.
As a “recent graduate”, I wouldn’t necessarily expect Brittany’s writing to be on par with, say, Malcolm Gladwell, but I would expect it to be at the level of, well, a college graduate. (I have seen some collegiate writing that appalled me when I was in school – writing submitted by 4th year English Majors that looked like it was pulled from a 6th grade student’s portfolio: but those folks don’t [typically] get hired by newspapers… do they?)
I hope Ms Penland’s writing improves dramatically through her “freelance” association with the Observer, but I also hope that the Observer doesn’t have too many folks like her writing in association with them: it reflects poorly on their editorial staff and hiring practices if they do.
Topics: commentary, complaint, hmmm | 2 Comments »
staybridge suites – avoid like the plague
I rarely have good reason to complain about hotels, restaurants, etc.
This is one of those rare occasions. And it was made worse because my wife had to go through it, too 
The following is the message I sent to the general manager of the Fishers IN Staybridge Suites location on Tuesday 19 July 2011 (after sending it to the corporate customer service department):
Our stay at the Staybridge Suites in Fishers IN has been horrible so far.
The facilities have been adequate, but the service has been appalling. Shortly after checking-in on the 18th, my wife was hit in the head by a stray thrown basketball while walking through the parking lot to walk our small dog. While walking our dog, she was also shouted-at by some of the teens staying at the hotel. After reporting this to the front desk, nothing was done – no apology was given, or was any attempt made to control the myriad teens running amok through and around the hotel.
The teen group has been out of control every time we have seen them, except at breakfast: taking-over the pool area, screaming, shouting, horseplaying, throwing basketballs out of the court (and hitting cars), making loud a ruckus after 10p last night in the common area (which could be heard completely down the hall and in every room facing over the great room).
Hotel staff have been unwilling or unable to control the behavior of the teens, and their apparent attempts to contact the chaperons and coaches have gone unheeded: the chaperons have been nowhere to be found (contrary to posted rules), and have done nothing to control the unruly children either.
At 1030p Monday evening, my wife went to the front desk to ask for extra pillows. The front desk lady indicated they would be sent up to our room “shortly”. At midnight, I went down and asked where they were: not only had housekeeping not brought anything up to our room, they had not been contacted even though there is a radio at the desk for such purposes. I waited an addition 12 minutes for someone in housekeeping to find a couple spare pillows and bring them to the desk so I could take them upstairs.
As I mentioned earlier, we are traveling with a small dog (a 2.5 year old Shih Tzu). The pet rules at Staybridge, vs any of the other ICH brands) are excessively stringent. An option is given at check-in as to whether daily housekeeping checks will be done either between 9a and 2p or after 5:30p. We selected the after 5:30p option. At 12:20p today, housekeeping knocked on our door. After being told to “wait just a moment”, they knocked again, and were told again “wait just a moment”. Then they opened the door WITHOUT INDICATING WHO THEY WERE until after the door was partially open. My wife was in the room by herself enjoying a TV show, and this behavior is unacceptable. After being shown that our housekeeping contract shows no one should come before 5:30p, they insisted on attending to the room anyway, and two maids came in, reset the sheets and replaced the towels, then left. If this is the daily housekeeping that is “required” for suites with pets, I shudder to think what “housekeeping” is done typically.
The behavior and attitude of the staff at this location is truly unbelievable for *any* hotel, let alone one in this price range. I travel extensively for business, and stay at hotels 2-4 times per month just for work. This is my first (and I expect my last) experience staying at a Staybridge Suites location. I have stayed at Candlewoods several times in CT and here in IN (just last week down one exit from the Staybridge). Candlewood has always been eagerly attentive to guest needs and requests, has a far more lenient pet policy, and is less expensive than Staybridge. We only selected to stay at a different location this week due to the Candlewood being sold out. We should have stayed the full week on the other side of town at a Candlewood to avoid this horrible experience with Staybridge.
It has been over a year (with hotel stays near weekly for much of that time) since having even a mediocre experience at any hotel – let alone such an egregious example of not caring and not trying on the part of hotel staff – and I am extremely disappointed with the Staybridge in Fishers.
His response to this message was NOT to call me at my cell phone number given on the day of the report (which the manager on duty (a sales coordinator) said he would do prior to my sending of the initial email), but rather to call my room the next morning (Wednesday) – after I had gone to work.
Hello, Mr Miller
My wife called and relayed the conversation you had with her this morning.
We will definitely contact you if anything else comes up and/or we need anything else during our stay.
If you have further questions or need to contact us, please call me at [redacted]
In the intervening days, nothing has been done beyond comp’ing us for the first night’s stay: which is a nice gesture, but doesn’t really do anything for me as this is a business trip (though I am sure my customer will appreciate the discount). The message I sent to Gary Miller today:
Mr Miller
While the noise from the rowdy teens has disappeared (I am guessing from not having seen them the past couple days that they left), housekeeping has been atrocious during our stay. Referring back to my initial email (which you have still not replied to outside of a call to my room on Wednesday morning when I was not available, in contradiction to what Kim Ilagon said you would do by calling my contact number she took down (and that has been on each of the emails I have sent you) or the contact number on my reservation), a “light touch service” is supposed to be mandatory every day in every room, with some form of more extended service if there is a pet in the suite. As you know, Tuesday’s housekeeping visit occurred over 5 hours before they were supposed to come to the room. That service visit was a mere “light touch” – replacing towels, emptying wastebaskets, and straightening the bed.
On Wednesday there was no housekeeping visit at all, and I was forced near the end of the evening to go ask for new towels at the front desk myself. Likewise on Thursday: no housekeeping visit occurred – and we again had to get new towels on our own.
Over the intervening days since Tuesday, the wastebaskets in our room have filled from day-to-day items – with no visit or way of getting housekeeping to take care of the room.
Additional cleanliness problems:
- There is a cup of beer on the windowsill at the end of the hall by room 201 that has been there since before we checked in
- The tray we used to bring breakfast up to our room was set outside our door yesterday – by lunchtime it had not been collected, so we moved it to the windowsill as well; it had still not been picked-up by when I left for work this morning
- Myriad soaked towels were on the floor of the pool last night for over 90 minutes with no one using them or coming to take care of them (my wife and I were swimming by ourselves for that duration)
- Trash bags have been left in stairwells for over a day before being collected
I appreciate the token you gave of comp’ing us for our first night – but as I am traveling on business, that doesn’t really “do anything” for myself or my wife (though my customer will be happy to have saved a night’s cost).
Last night I went to the front desk to ask if it might be possible to do a late checkout, which the staff member told me was not an issue, and wrote down that we would be checking-out at 2p. Today housekeeping came by at about 1215 to do a service on the room, and were surprised my wife was still in the room.
90 minutes later the front desk called my wife asking if we were going to extend our stay – the woman at the front desk had not bothered to read any of the comments/notes left for her from the night before.
Communication at this hotel amongst the staff is atrocious. I have copied this message back to corporate customer service as well (as I did the first message to you).
Contact information for this hotel:
Front desk: 317.577.9500
General Manager: Gary Miller gmiller@imd1.com
Topics: commentary, complaint, travel, warning | 1 Comment »
