DarylDawkins.net

Here I will school you on some of the most important aspects of running Oracle 11g. This is not going to be another Oracle 11g new features list, I’ll be just posting any of my research findings here, in a semi-organized way as I just spent some back breaking hours getting this thing running and tuned properly.

The first post is is about Automatic Memory Management. AMM manages all SGA + PGA memory together, allowing it to shift memory from SGA to PGAs and vice versa. You only need to set a MEMORY_TARGET (and if you like, MEMORY_MAX_TARGET parameter).

You can read rest of the general details from documentation, I will talk about how this feature has been implemented on OSD / OS level (or at least how it looks to be implemented).

When I heard about MEMORY_TARGET , then the first question that came into my mind was that how can Oracle shift shared SGA memory to private PGA memory on Unix? This would mean somehow deallocating space from existing SGA shared memory segment and releasing it for PGA use. To my knowledge the traditional SysV SHM interface is not that flexible that it could downsize and release memory from a single shared memory segment. So I started checking out how Oracle had implemented this.

One option of course is not to implement it at all – just do not use the extra space in the extra SGA area and it will be soon paged out if there’s memory pressure (as long as you don’t keep your SGA pages locked – which can’t be used together with MEMORY_TARGET anyway). However should this “unneeded” memory be used again, all would have to be loaded back from swap area.

I started by checking what are the shared memory IDs for my instance:

$ sysresv

IPC Resources for ORACLE_SID "LIN11G" :
Shared Memory:
ID              KEY
1900546         0x00000000
1933315         0xa62e3ad4
Semaphores:
ID              KEY
884736          0x6687edcc
Oracle Instance alive for sid "LIN11G"

Ok, let’s look for corresponding SysV SHM segments:

$ ipcs -m

------ Shared Memory Segments --------
key        shmid      owner      perms      bytes      nattch     status
0x00000000 1900546    oracle    660        4096       0
0xa62e3ad4 1933315    oracle    660        4096       0

The segments are there, but wait a minute, they are only 4kB in size each! If there are no large shared memory segments used, where does Oracle keep its SGA?

The immediate next check I did was looking into the mapped memory for an Oracle instance process – as the SGA should be definitely mapped there!

$ pmap `pgrep -f lgwr`
29861:   ora_lgwr_LIN11G
00110000      4K rwx--    [ anon ]
00111000     32K r-x--  /apps/oracle/product/11.1.0.6/lib/libclsra11.so
00119000      4K rwx--  /apps/oracle/product/11.1.0.6/lib/libclsra11.so
...
...
49000000  16384K rwxs-  /dev/shm/ora_LIN11G_3997699_0
4a000000  16384K rwxs-  /dev/shm/ora_LIN11G_3997699_1
4b000000  16384K rwxs-  /dev/shm/ora_LIN11G_3997699_2
4c000000  16384K rwxs-  /dev/shm/ora_LIN11G_3997699_3
4d000000  16384K rwxs-  /dev/shm/ora_LIN11G_3997699_4
...
...
88000000  16384K rwxs-  /dev/shm/ora_LIN11G_3997699_63
89000000  16384K rwxs-  /dev/shm/ora_LIN11G_3997699_64
bfc1f000     88K rwx--    [ stack ]
 total  1225048K

pmap output reveals that Oracle 11g likes to use /dev/shm for shared memory implementation instead. There are multiple 16MB “files” mapped to Oracle server processes address space.
This is the Linux’es POSIX-oriented SHM implementation, where everything, including shared memory segments, is a file.

Thanks to allocating SGA in many smaller chunks, Oracle is easily able to release some parts of SGA memory back to OS and server processes are allowed to increase their aggregate PGA size up to the amount of memory released.
(Btw, if your MEMORY_MAX_TARGET parameter is larger than 1024 MB then Oracle’s memory granule size is 16MB on Linux, otherwise it’s 4MB).

Note that the PGA memory is still completely independent memory, allocated just by mmap’ing /dev/zero, it doesn’t really have anything to do with shared memory segments ( unless you’re using some hidden parameters on Solaris, but that’s another story ).
PGA_AGGREGATE_TARGET itself is just a recommended number, leaving over from MEMORY_TARGET – SGA_TARGET (if it’s set). And Oracle uses that number to decide how big PGAs it will “recommend” for sessions that are using WORKAREA_SIZE_POLICY=AUTO.

So how does Oracle actually release the SGA memory when it’s downsized?

Compare these outputs:

/dev/shm before starting instance:

$ ls -l /dev/shm/
total 0

Obviously there’s nothing reported as no /dev/shm segments are in use.

/dev/shm after starting instance with fairly large SGA (note that some output is cut for brewity).
See how some of the memory “chunks” are zero in size. These chunks are the ones which have been chosen as victims for destruction (or for not-even-creation) when space was needed or PGA areas. If you look into pmap output for any server processes you will still see this memory mapped into the address space, but it’s not just used because Oracle knows this memory is really freed.

$ ls -l /dev/shm
total 818840
-rw-r----- 1 oracle dba 16777216 Aug 20 23:29 ora_LIN11G_1900546_0
-rw-r----- 1 oracle dba        0 Aug 20 23:29 ora_LIN11G_1933315_0
-rw-r----- 1 oracle dba        0 Aug 20 23:29 ora_LIN11G_1933315_1
-rw-r----- 1 oracle dba        0 Aug 20 23:29 ora_LIN11G_1933315_10
-rw-r----- 1 oracle dba        0 Aug 20 23:29 ora_LIN11G_1933315_11
-rw-r----- 1 oracle dba        0 Aug 20 23:29 ora_LIN11G_1933315_12
-rw-r----- 1 oracle dba        0 Aug 20 23:29 ora_LIN11G_1933315_13
-rw-r----- 1 oracle dba        0 Aug 20 23:29 ora_LIN11G_1933315_14
-rw-r----- 1 oracle dba 16777216 Aug 20 23:37 ora_LIN11G_1933315_15
-rw-r----- 1 oracle dba 16777216 Aug 20 23:37 ora_LIN11G_1933315_16
-rw-r----- 1 oracle dba 16777216 Aug 20 23:37 ora_LIN11G_1933315_17
-rw-r----- 1 oracle dba 16777216 Aug 20 23:37 ora_LIN11G_1933315_18
-rw-r----- 1 oracle dba 16777216 Aug 20 23:37 ora_LIN11G_1933315_19
-rw-r----- 1 oracle dba        0 Aug 20 23:29 ora_LIN11G_1933315_2
-rw-r----- 1 oracle dba 16777216 Aug 20 23:37 ora_LIN11G_1933315_20
-rw-r----- 1 oracle dba 16777216 Aug 20 23:37 ora_LIN11G_1933315_21
-rw-r----- 1 oracle dba 16777216 Aug 20 23:37 ora_LIN11G_1933315_22
-rw-r----- 1 oracle dba 16777216 Aug 20 23:37 ora_LIN11G_1933315_23
-rw-r----- 1 oracle dba 16777216 Aug 20 23:37 ora_LIN11G_1933315_24
...

Another listing, taken after issuing “alter system set pga_aggregate_target=600M”
You can see from below that most of the /dev/shm files which were 16MB in previous listing, have also been zeroed out.

$ ls -l /dev/shm
total 408740
-rw-r----- 1 oracle dba 16777216 Aug 20 23:29 ora_LIN11G_1900546_0
-rw-r----- 1 oracle dba        0 Aug 20 23:29 ora_LIN11G_1933315_0
-rw-r----- 1 oracle dba        0 Aug 20 23:29 ora_LIN11G_1933315_1
-rw-r----- 1 oracle dba        0 Aug 20 23:29 ora_LIN11G_1933315_10
-rw-r----- 1 oracle dba        0 Aug 20 23:29 ora_LIN11G_1933315_11
-rw-r----- 1 oracle dba        0 Aug 20 23:29 ora_LIN11G_1933315_12
-rw-r----- 1 oracle dba        0 Aug 20 23:29 ora_LIN11G_1933315_13
-rw-r----- 1 oracle dba        0 Aug 20 23:29 ora_LIN11G_1933315_14
-rw-r----- 1 oracle dba        0 Aug 20 23:46 ora_LIN11G_1933315_15
-rw-r----- 1 oracle dba        0 Aug 20 23:46 ora_LIN11G_1933315_16
-rw-r----- 1 oracle dba        0 Aug 20 23:46 ora_LIN11G_1933315_17
-rw-r----- 1 oracle dba        0 Aug 20 23:46 ora_LIN11G_1933315_18
-rw-r----- 1 oracle dba        0 Aug 20 23:46 ora_LIN11G_1933315_19
-rw-r----- 1 oracle dba        0 Aug 20 23:29 ora_LIN11G_1933315_2
-rw-r----- 1 oracle dba        0 Aug 20 23:46 ora_LIN11G_1933315_20
-rw-r----- 1 oracle dba        0 Aug 20 23:46 ora_LIN11G_1933315_21
-rw-r----- 1 oracle dba        0 Aug 20 23:46 ora_LIN11G_1933315_22
-rw-r----- 1 oracle dba        0 Aug 20 23:46 ora_LIN11G_1933315_23
-rw-r----- 1 oracle dba        0 Aug 20 23:46 ora_LIN11G_1933315_24
-rw-r----- 1 oracle dba        0 Aug 20 23:46 ora_LIN11G_1933315_25
-rw-r----- 1 oracle dba        0 Aug 20 23:46 ora_LIN11G_1933315_26
-rw-r----- 1 oracle dba        0 Aug 20 23:46 ora_LIN11G_1933315_27
-rw-r----- 1 oracle dba        0 Aug 20 23:46 ora_LIN11G_1933315_28
-rw-r----- 1 oracle dba        0 Aug 20 23:46 ora_LIN11G_1933315_29
-rw-r----- 1 oracle dba        0 Aug 20 23:29 ora_LIN11G_1933315_3
-rw-r----- 1 oracle dba        0 Aug 20 23:46 ora_LIN11G_1933315_30
-rw-r----- 1 oracle dba        0 Aug 20 23:46 ora_LIN11G_1933315_31
-rw-r----- 1 oracle dba        0 Aug 20 23:46 ora_LIN11G_1933315_32
-rw-r----- 1 oracle dba        0 Aug 20 23:46 ora_LIN11G_1933315_33
-rw-r----- 1 oracle dba        0 Aug 20 23:46 ora_LIN11G_1933315_34
-rw-r----- 1 oracle dba 16777216 Aug 20 23:29 ora_LIN11G_1933315_35
-rw-r----- 1 oracle dba 16777216 Aug 20 23:29 ora_LIN11G_1933315_36
-rw-r----- 1 oracle dba 16777216 Aug 20 23:29 ora_LIN11G_1933315_37
-rw-r----- 1 oracle dba 16777216 Aug 20 23:29 ora_LIN11G_1933315_38
...

So, in Linux (tested on OEL5) Oracle 11g is using a new mechanism for managing shared memory. Well this mechanism itself isn’t that new, but it’s unconventional considering the long history of Unix SysV SHM segment use for Oracle SGAs.

---

Does this all matter? Yes
Why does it matter? There are few administrative differences compared to the conventional implementation.First of all, ipcs -m doesn’t show the full size of these segments anymore. You need to list /dev/shm contents for that.Also, pmap always reports that the memory is mapped (because it is) even though it doesn not have physical backing storage on tmpfs on /dev/shm device.

One more important note is that if you have not configured your tmpfs size on /dev/shm properly, then Oracle fails to allocate new POSIX-style shared memory and will not allow you to use MEMORY_TARGET parameters (startup without those parameters will however succeed).

The error message you likely get looks like that:

SQL> ORA-00845: MEMORY_TARGET not supported on this system

And is accompanied by following entry in alert.log:

Sat Aug 18 12:37:31 2007
Starting ORACLE instance (normal)
WARNING: You are trying to use the MEMORY_TARGET feature. This feature requires the /dev/shm file system to be mounted for at least 847249408 bytes. /dev/shm is either not mounted or is mounted with available space less than this size. Please fix this so that MEMORY_TARGET can work as expected. Current available is 0 and used is 0 bytes.
memory_target needs larger /dev/shm

So you need to configure large enough tmpfs on /dev/shm device to fit all memory up to MEMORY_MAX_TARGET.

The configuration works roughly like that:
(run as root):

# umount tmpfs
# mount -t tmpfs shmfs -o size=1300m /dev/shm
# df -k /dev/shm
Filesystem           1K-blocks      Used Available Use% Mounted on
shmfs                  1331200         0   1331200   0% /dev/shm

This one allows /dev/shm to grow roughly up to 1300MB, allowing you to use MEMORY_MAX_TARGET (or MEMORY_TARGET) set to 1300MB. The Linux-specific Oracle 11g documentation has more details how to configure this.

---

Note that after resetting various parameters I played with I realized that finally Oracle has implemented the human-friendly way for resetting parameters in SPFILE:

Sys@Lin11g> alter system reset pga_aggregate_target;

System altered.

Sys@Lin11g> alter system reset sga_target;

System altered.

…no scope=spfile sid=’*’ is needed. This resets the parameter in spfile only, the values in memory persist.

The iPhone’s lack of integrated support for multimedia messaging (MMS) is quite the pain. Fortunately, using the iPhone’s built-in support for email you can work around this lack of functionality. With a little preparation on both you and your friends’ parts, you can send and receive picture messages without too much trouble.

The not-so-secret secret here is that most wireless providers assign their subscribers an email address based on their phone number. If you send an email to that address, it’ll get delivered as a text message—if you attach a photo to that message—say, using the iPhone’s built-in photo emailing—it’ll get delivered as a picture message. The trick is just knowing the address of the contact you want to send the message to. I have taken the liberty to compile a list of the most common providers.

Alltel = xxxxxxxxxx@message.alltel.com

AT&T = xxxxxxxxxx@mms.att.net

Boost Mobile = xxxxxxxxxx@myboostmobile.com

Cingular (AT&T) = xxxxxxxxxx@mms.mycingular.com

Einstein PCS = xxxxxxxxxx@einsteinmms.com

Sprint = xxxxxxxxxx@messaging.sprintpcs.com

T-Mobile = xxxxxxxxxx@tmomail.net

US Cellular = xxxxxxxxxx@mms.uscc.net

Verizon Wireless = xxxxxxxxxx@vzwpix.com

Virgin Mobile = xxxxxxxxxx@vmobl.com

And to make it even easier, you can just enter this address as an additional email in your contact’s address record.

For receiving messages, the same principle works in reverse. Your iPhone, after all, has a robust email client built-in. And just like the wireless provider has email addresses for every phone, most phones can send text and picture messages to email addresses. So instead of having your friend send that snapshot to your phone, have them send it to any email account that you have set up on your iPhone.

It’s hardly an ideal solution, and I’d hope that Apple adds in real MMS support soon. I dont have a 3GS and maybe it is in there, nut if not then this may hold you over for now.

HP 1245DX Review

The good: Attractive design skips the usual gray and black; good battery life for a desktop replacement; touch-sensitive multimedia controls; Linux Friendly(relatively)

The bad: Slower performance than core 2 duo; low-res screen not ideal for HD content.

The bottom line: HP’s attractive, multimedia-friendly Pavilion dv7-1245dx is an inexpensive choice for a desktop replacement, as long as you don’t need too much horsepower under the hood.

Here is my review of the HP Pavillion DV7 1245 dx. I purchased in Feb 2009 and now just getting around to this review after some months with it.

My requirements for a laptop were simple. I didnt need the most powerful machine because my QuadCore Desktop will get utilized for any truly CPU intensive task. I needed somthing that had a large screen, full sized keyboard, good battery life and 64bit CPU. I needed something that would compliment my desktop system when I was away. Pretty simple. In that regards I did not need to spend alot of money so my goal was to find these qualities in a machine under $800.

The 1245DX seemed at the time the best choice for what I needed. It had all the requirements, including $700 price tag at the time. While the Turion X2 processor may not have been as fast as a similar spec core 2 duo, it is no slouch. Seeing how I was moving from a 32 bit single core CPU to this, I noticed a huge gain in performance in task such as Video encoding and ISO file creation.

The design of the dv7-1245dx is very similar to the smaller 15-inch dv5-1235dx. HP wisely makes the current dv line of laptops stand out from the crowd, skipping the typical glossy gray-and-black designs for a subtle cross-hatch pattern with a bronze tint, which is more likely to fit into your post-dorm-room decor. I also like the laptop’s single, long hinge, which keeps the display from wobbling.

The touch pad (which has wide-screen-like dimensions) and mouse buttons have a highly reflective mirrored finish. It shows fingerprints and smudges easily, but also offsets the bronze chassis color nicely. One other complaint: the mirrored finish on the touch pad glides less easily against the finger than a traditional touch-pad finish, causing a little bit of finger drag.

For a budget system, the series of lighted, touch-sensitive media controls above the keyboard look especially nice, glowing either white or orange depending on status (Wi-Fi on vs. off, for example which only works on windows.). There’s also a volume slider, but for sensitive volume tweaks I still prefer a physical wheel; touch-controlled volume sliders are finicky and lack the ability to do very fine adjustments. When the system is off or asleep, the button labels literally vanish into the mirrored strip above the keyboard.

The 17-inch wide-screen LCD display offers a 1,440×900 native resolution, which is typical in less expensive desktop replacements, but the more common 1,600×1,200 screens are better for watching HD video content. The glossy screen makes video content pop, but can cause distracting glare while trying to read or type, depending on the lighting in the room.

First Off there are some quick tips that you can do to make this faster right out of the box(for a little more cash however). The stock 5400 RPM drive provided the greatest opportunity for improvement so I decided to go with a Western Digital Scorpio 320GB 7200 RPM drive

This added an additional $89(newegg.com) to the price but was well worth it, especially since this laptop has 2 drive bays! The downside to running two drives however is decreased battery life. Right now my Scorpio has plenty of space still so I am only running 1 drive in it for now.

The other good part of adding a new drive to this is that you can keep the preinstalled copy of windows vista on the stock drive in case you need to sell the machine later on.

As the title implies, my plan was to install linux on this bad boy and see what I could squeeze out of it as far as performance goes and how that would compare to my previous 32bit P4.

So first thing was to crack open the machine and replace the hard drive, pretty simple task.

The two drive bays are visible in the picture above. I simply unscrewed the two black mounting screws from the mount tray and pulled the tab to remove the drive.

I then removed the original drive from the drive tray and replaced it with my new Scorpio (note that to use both drives at the same time, an additional drive tray is needed and not included, I found one using google)

After getting the drive back in, I was ready to install my OS. I first tried Fedora but due to some issues with the version of the kernel in Fedora 11 and unavailable ATI drives for it, I went with a more stable distro in Debian Lenny.

In both distros the install went very well, all hardware included wireless card, camera and mic were all detected.

One thing to note is that the included remote will not work unless you are running windoze.

As well, the touch controls may or may not need to be configured per app. Surprisingly in both KDE and GNOME my touch volume slider worked to control the volume. The media control buttons also work but need to be mapped per application first.

The wireless touch button also works in linux, however it does not change colors to indicate on or off. Mine stays an Amber color whether on or off. After a long bout of trying to figure out why my laptop could not see my SSID on my router which was 3 feet away, I used ‘iwlist’ tool to determine that the wireless card was not even on.

The 1245dx also has an ESATA port which is convenient for connecting external storage devices. I have found that linux kernel support for this does not seem to work until at least kernel version 2.6.30 which is in Fedora 11, but unfortunately not Debian lenny.

I ultimately choose Debian Lenny over Fedora because stability is more important than bleeding edge on my laptop. I dont want to be out on the road trying to fix drivers or something else crazy like that. Fedora is an excellent distro but better suited for my desktop right now.

Debian is stable, fast, small footprint, and has an excellent package management system. It also does not hold your hands like an Ubuntu distro. Very flexible and similar in alot of ways to my favoured OS, Slackware, Debian is the perfect compliment to this machine.

I use this machine mainly for development work, writing and compiling c/c++ code, as well as some multi media work such as encoding videos, creating and burning ISO files, and watching the occasional movie.

The 1440×900 resolution is certainly lower than the res on most 17″ monitors but certainly still HD quality(higher than 720p) and very much enjoyable to watch on. ATI drivers dont seem to be quite as up to par as nvidia drivers but they get the job needed for this non gaming system. Most of the issues I had revolve around getting the correct driver with support for the kernel you are running. Right now catalyst 9.9 has been released and this seems to work ok except for a few issues when running compiz.

All said, I am pretty happy with what I got for the price I paid. Under $800 including the Scorpio hard drive and I have a very capable system of being my desktop away from home

There is just so much going on in science that no single person can keep up with it all. So when a friend of mine sent me a copy of an article about the beginnings of a remote-controlled moth, I just had to write about it. One problem though—the research paper is from August of last year, so there may be some bemusement on the part of the researchers that the media has cottoned on to their research so late. What can I say? I don’t go looking for remote-controlled moths, I wait for them to come to me.

This research comes under the heading of micro-air-vehicles development, and it turns out that building tiny airplanes is quite difficult. This is, in large part, due to the joys of momentum. A large aircraft has a lot of mass, so the conservation of momentum turns every breath of turbulence and minor change in air pressure into minimal changes in altitude, attitude, and speed.

But this is not so for tiny vehicles. Designing control systems and electronics that can manage a vehicle that can be turned upside down by someone sneezing is probably possible. Fitting those electronics into the vehicle is not. Even running the whole shebang remotely is difficult, due to the sensor and data transfer requirements. As a result, some in the field are turning to nature’s micro-air-vehicles—insects—and gazing with admiration at their abilities. Insects face all the same problems, but get around them by having a complex and highly variable wing-stroke pattern that compensates for (bad pun alert) on-the-fly turbulence.

And this is where things turn a bit surreal, with researchers discussing the carrying capacity, air-speed velocity, and range of various moths. (You have to provide your own coconuts and mockery-filled castle though.) It turns out that the Tobacco hornworm moth is the ideal insect to turn into your own micro-air-vehicle. It’s big, so it can carry quite a bit of excess weight without adversely affecting its flight characteristics. It has a range of several kilometers and, for an insect, is quite quick. But how to control it?

Well, in this case, the researchers chose to directly manipulate the metabolism of the moth. They injected adult moths with a collection of insect venom, spider venom, and man-made insecticides to examine the effect on the moth’s metabolism. From these experiments, they found that several of the venoms could be used to reversibly slow the moth’s metabolic rate—depending on the amount injected, the venom could act locally or globally.

From there, the researchers moved on to testing a remote controlled injection system. Before the adult moth emerged from its pupal stage, they cut it open, inserted a microfluidic device, and then literally glued the moth closed again. Most moths survive this process, but not all of them wound up with unrestricted wing motion.

The researchers tethered the viable moths in a chamber with an agitator that kept them flying. When the microfluidic injection process was activated, it slowed the moth’s metabolism. The moth could be slowed down by a chosen amount—to the point where they could induce paralysis in the moth and then reanimate it.

Of course, this doesn’t allow the researchers to control where the insect flies to, nor does it induce the insect to fly at all. But, with a more complicated microfluidic injection system, the metabolic rate of each wing could be used to control direction, while an electrode could be used to stimulate the insect’s flight response.

Now, this sounds rather complicated—surely if you can stick a microfluidic device in a moth, you could directly control the wings with electrodes? It turns out that you can, but you end up having to control every aspect of the flight, which is not all that desirable.

This may turn out to provide a compromise, where the controller can control the general direction of the flight—perhaps not very precisely—or prevent the insect from having a wee rest on a branch. And that is certainly much better than nothing.

I realize that the start of this article took a rather lighthearted tone, which could be interpreted as poking fun that the research and researchers. It is, sometimes, hard not to see the inherent comedy associated with an outsider’s perspective on research. But that doesn’t take away from the achievements of the researchers: this is a very impressive demonstration of the understanding and control of metabolism in this particular moth species. Nevertheless, I can’t help picturing a future in which urban terrorists come packing fly spray.

Life can change in a split second. In the blink of an eye you can be on a different path.
I almost died yesterday, but I didn’t. So after the initial “oh wow”, it is a non issue to anyone I bring it up to.
Obviously I didn’t die. People die and almost die everyday. But im still here, luckily.

 

So it looks like Skype is coming to the iPhone tomorrow, March 31st, and for the blackberry in May. Well I guess this explains why there is no native 64bit Linux version yet. To busy porting to mobile devices

But good news none the less. iPhone users will be abe to download Skype’s software for free,  make free calls to other Skype users, but will be charged as normal for calls to non Skype users.

It will be interesting to see how Skype will measure up to the competition, namely Fringe, which can handle x-network IM and includes the ability to make calls to Skype buddies, and has been available on the iPhone for months now.

Some features:

• Ability to use address book for Skype contacts
• Chat
• Taking a photo from within Skype to serve as your avatar image(iPhone only)
• Pulling a picture in from the camera roll(iPhone only)
• Ability to join a conference call

Missing Features:

• Although you cant actually initiate a conference call from iPhone skype, you can join one in progress.
• No SMS
• Cannot purchase Skype Credits
• Cannot take more than 1 call at a time
• No file transfers
• cannot listen to your Skype Voicemail

Hopefully we will see some of these features in the new version, but for now just waiting until tomorrow to actually
try this out and see how well it works.
 
Read CNET Story….

What is 1-Wire

1-Wire bus is a communication system developed by Dallas Semiconductor. It is quite similar to I2C, except for the data rate, which is lower, the costs, which are very low, and the range, which is higher. The 1-Wire protocol allows the communication among several devices produced by Dallas Semiconductors/Maxim, such as:

* temperature, humidity, and pressure sensors, thermocouples
* LCD, counters
* eeprom and rom memory, encryption (IP protection)
* identification devices (electronic keys)

The main applications of 1-Wire devices are as follows:

* Print Cartridge ID
* Medical Consumable ID
* Rack Card Calibration and Control
* Printed Circuit Board (PCB) identification and authentication
* Accessory/Peripheral Identification and Control
* IP Protection, Secure Feature Control, Clone Prevention
* Consumer electronics
* Access control
* Electronic cash
* Gaming devices

 

1-Wire is a half-duplex, bi-directional bus, and the communication is established among a device, the master, which controls through the bus one or more slave(s). The following figure shows the block diagram of the 1-Wire communication bus, with a detail of the master (HOST in the picture) and a generic slave.

 

 The master device is connected to the bus through an open-drain configuration and to the supply power (Vcc, which ranges from 2.8 to 5.25 V) through the pull-up resistor R (normally its value is 4.7 Kohm). On the other hand, the slave receives all the power it needs from the bus, which is the only wire present. As visible in the above figure, the capacitor inside each slave (usually it is a 800 pF capacitor) will be charged when the bus is in the idle state (corresponding to a high or positive level of the 1-Wire bus). When, instead, the bus is at a low level, that is when the communication between master and slave is taking place, the slave uses the energy stored in the capacitor to power itself. Differently from other bus protocols such I2C or SPI, the 1-Wire bus requires that each slave be physically connected to the bus: if a slave is disconnected, it cannot be operative any longer, thus entering a reset state; when it is connected again to the bus, it wakes up and, receiving the supply power directly from the bus, can declare its presence to the bus controller (the master device).

The principal advantages of the 1-Wire technology are:

• Inexpensive devices, simple wiring, parasitic power
• Unique addresses, individually addressable
• USB, serial and i2c adapters
• Mature technology, consulting and aftermarket support
• iButton steel sealed devices
• Single Contact Sufficient for Control and Operation
• Unique ID Factory-Lasered in Each Device
• Power Derived from Signal Bus (”Parasitically Powered”)
• Multidrop Capable: Supports Multiple Devices on Single Line
• Exceptional ESD Performance
• IP Protection, Secure Feature Control, Clone Prevention

Each slave connected to a 1-Wire bus has a unique and unalterable serial number: through this ID, it can be univocally selected and addressed by the master device. The 64-bit ROM number is written during the manufacturing process and it includes the following fields: an 8-bit Family Code which identifies the slave type and functionality (up to 256 slave types are supported), a 48-bit Serial Number, an 8-bit CRC. No clock is necessary in 1-Wire bus, since time synchronization is performed by the slaves on the falling edge of the bus wire controlled by the master. There are two kinds of data rate: standard, with a transmission speed up to about 16 Kbps, and overdrive, which increases the speed by a factor of 10.
The first operation to be executed by an application on the 1-Wire bus is the selection of the slave device. Once a slave has been selected, the master sends specific commands on the bus to write data to or read data from the slave. The reset command is accepted by all the slaves connected to the bus.

OWFS: a nice open-source project related to 1-Wire

Owfs (acronym of One Wire File System) is a project created by Paul H. Alfille and The Owfs Team (Owfs homepage: http://owfs.sourceforge.net/). It is an open-source project developed under Linux operating system with the following purpose: access any 1-Wire device as if it were a regular file belonging to the file system. So, to perform a read operation from all 1-Wire temperature sensors connected to the bus, a shell command like “cat */temperature” would be enough. For instance, the collection of temperature sensors above are all on one bus, individually addressable, and will reconfigure on the fly as items are added or removed. OWFS is an original and useful way to work and experiment the powerful 1-Wire devices of Dallas Semiconductor/Maxim. Moreover, shell commands are powerful and can be organized in script files to be executed (also automatically or on a batch basis) during the development, testing, and validation phases of a 1-wire application.
The main characteristics of Owfs are:

• Filesystem access
• Web access (through the application owhttpd)
• Remote network access (through the application owserver)
• Direct language support for perl, python, php, tcl, C (libow, ownet)
• Bootable CD
• Support for many processors and OS
• Free under GPL license

Universal 1-Wire COM Port Adapter

Dallas Semiconductor-Maxim offers an interesting tool (DS9097U) for 1-Wire testing and debugging. It connects to the RS232 serial port of a PC (both DB-9 and DB-25 connectors are supported) and, together with a TMEX software driver, allows reading and writing on 1-Wire devices which are connected through a RJ-11 port; both regular and overdrive data rates can be used. With the DB-9 connector it is possible to communicate only with non-eeprom 1-Wire devices, whereas the DB-25 connector allows also to write on 1-Wire eeprom even though an external power supply is requested in that case. The DS9097U adapter is based on the DS2480B Serial 1-Wire Line Driver chip.
Drivers can be freely downloaded from: http://www.ibutton.com/software/tmex/index.html.

Since there aren’t any native 64 bit packages of skype for linux, it has been somewhat of a challenge to get a workable solution. I’ve gone through the pain so you can enjoy.

My Specs:

HP DV7-1245DX laptop
AMD Turion X2 64 bit dual core 2.1 Ghz
Fedora 10 x86_64
KDE 3.5
Linux TeK360 2.6.27.19-170.2.35.fc10.x86_64 #1 SMP Mon Feb 23 13:00:23 EST 2009 x86_64 x86_64 x86_64 GNU/Linux

You can install Skype with either static or dynamically linked libraries. I recommend the dynamic version, since it makes use of the existing system libraries that are managed by Fedora. This will minimize any potential library conflicts.
The only thing necessary for you to check is to make sure you have all the 32-bit versions of the libraries Skype requires.
you can use “ldd” to analyze the library requirements for skype. I have conveniently done this step for you and compiled the appropriate yum statement.

as root:

yum install alsa-lib.i386 dbus-libs.i386 e2fsprogs-libs.i386 expat.i386 fontconfig.i386 freetype.i386 glib2.i386 glibc.i686 keyutils-libs.i386 krb5-libs.i386 libcap.i386 libgcc.i386 libICE.i386 libpng.i386 libselinux.i386 libSM.i386 libstdc++.i386 libX11.i386 libXau.i386 libxcb.i386 libXcursor.i386 libXdmcp.i386 libXext.i386 libXfixes.i386 libXi.i386 libXinerama.i386 libXrandr.i386 libXrender.i386 libXScrnSaver.i386 libXv.i386 openssl.i386 qt.i386 qt-x11.i386 zlib.i386

Now, you can install the dynamic version of Skype from here

Choose “Dynamic”, near the lower left of the box in the middle of the page.
you should be downloading the file “skype-2.0.0.72.tar.bz2″

Now, open up a new terminal window, and “cd” into the directory that you downloaded Skype into, and extract and run Skype.

cd ~/skype
tar -jxvf skype-2.0.0.72.tar.bz2
cd skype-2.0.0.72
./skype

Skype should come right up, since you now have all the libraries.

Log in. Skype should now be up and running.

In the main Skype window, hit the “S” in the lower left corner to bring up the menu, then choose Options.

Skype sound device setting:

In Skype, go to Sound Devices. I recommend setting your sound devices to something that contains “hw:SB,0″ in its name. Do this for all 3 choices: sound in, sound out, and ringing. Choose the name of your device that best matches the hardware you want to use. Definitely avoid generic single-word names like “default”, “hdmi”, “pulse”, and so on.
mine looks like:
HDA ATI SB (hw:SB,0)

Skype video settings:

In Skype, go to Video Devices. Try selecting your webcam from the list, and hit Test. My integrated HP webcam was previously setup automatically when I installed Fedora. Fedora has really improved their webcam support in this latest release. Almost every known webcam should work by now.

Now, you’re ready to make a call. Call “echo123″ first, to make sure your sound works. Call your friends, to make sure your video works

And thats pretty much it. Enjoy Skype 2 on 64 bit linux!

Myths

• “You don’t need 64-bit software with less than 3 GB RAM”
• “There are less drivers for 64-bit OS”
• “You will need all new software, all 64-bit”
• “64-bit software is twice as fast”

read more…

Myths and facts about 64-bit Linux(®).

HARTFORD — Connecticut voters support decriminalizing possession of small amounts of marijuana, but in a weird twist on this emerging liberal agenda, they oppose allowing grocery stores to sell wine and distilled spirits, according to the new Quinnipiac University Poll.

The poll, released Tuesday morning, also shows voters support Sunday liquor sales, which have been proposed as a way to create new sources of state tax revenue.

When asked if they would favor a law similar to the statewide ballot initiative passed last November in Massachusetts — making possession of less than a ounce of pot an infraction punishable by a small fine similar to a traffic ticket, rather than a misdemeanor that must be adjudicated and create a police record — voters approved 58-37 percent.

Even voters over age 65 agree with the idea, although Republicans oppose it 51-44 percent. Democrats approve 68-30 percent, and unaffiliated voters support decriminalization 58-35 percent.

Douglas Schwartz, director of the poll, said it’s the first time it has asked voters in any state their feelings about decriminalizing marijuana.

“There is interest,” he said of support for reducing penalties for possession.

Senate Majority Leader Martin M. Looney, D-New Haven, said in an interview Tuesday that the poll reinforces legislation he has proposed this year that would mirror Massachusetts’ marijuana possession law.

“This is pretty substantial,” Looney said of the 58 percent approval rating. “The change in Massachusetts was passed with over 60 percent of voters in favor. Clearly the public sees this as a reasonable idea to prioritize within the criminal justice system.”Looney’s bill, which is co-sponsored by Sen. Toni N. Harp, D-New Haven, has been raised in the Judiciary Committee, but a public hearing has not yet been scheduled.

Last year Gov. M. Jodi Rell vetoed a so-called medical marijuana bill, which Looney said is entirely different from the decriminalization bill. The medical marijuana had a procedure for authorizing people to grow the weed in violation of overriding federal law.

“I think it has a chance this year partly because the public seems ahead of politicians on this issue,” Looney said, adding that an estimated $15 million could be saved in Connecticut by freeing public defenders and prosecutors from handling low-level pot possession cases.

The poll found that voters approve Sunday alcohol sales by 54-44 percent, although the poll found a “substantial” gender gap, with men supporting the sales by 62-37 percent. Women are nearly evenly split. Package store owners recently went to the Capitol to defeat legislation that would allow Sunday sales.

“Although Connecticut is known as the land of steady habits, Nutmeggers appear willing to change the law so that Connecticut package stores can sell alcohol on Sunday,” Schwartz said.

In an apparent inconsistency in the otherwise liberal reaction to questions on social issues, voters oppose allowing grocery stores to sell wine and distilled spirits by 58-39 percent.

The Q Poll surveyed 1,238 Connecticut registered voters from March 3 to 8, with a margin of error of plus or minus 2.8 percentage points.

The poll found Rell’s approval rating remains high, 75 percent, and voters approve, by 61-28 percent, the way she’s handling the budget crisis.

Attorney General Richard Blumenthal enjoys an 81 percent job-approval rating.

Poll: Connecticut should legalize small amounts of marijuana - NewsTimes.com.