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It seems that the good folks have just released Eclipse 3.1. I’ve been running Eclipse 3.1 for a while now, up through M3 and M4. But now its released.
I’ll be holding off a little bit, as the main plug in I use (the web tools project) is about to release their 0.7 M5 in the next couple of days, and once thats declared I think I’ll move to both 3.1 and WTP 0.7M5.
Heading off this morning, a bit later than planned, we found out that its cold this time of year in Melbourne. After last weeks decent ride, we didn’t want to cheat ourselves and so decided to Actually make it to Jells park this week.
The ride was relatively calm, with little wind and not too many others on the path. We made pretty good time, only stopping for the red light crossing Burwood Hwy.
We rolled into Jells park, and decided not to stop so just continued on around the lake and back home. Instead of just following the same track back, we decided to take the alternate route that goes up and along Stud Rd.
This detour was about the same length as the normal track, except that its up and down Stud Rd. We ended up back by 1:00, so about a 2 hr ride, and given that it was 35k’s not a bad effort.
I had a heap left in the tank and would have liked to do another 5–10k’s to really round out the ride. But it was good to do another serious stint in the saddle, I think this back to back riding makes it much easer as time goes on.
I’ve had some issues with DCAF in recent times. The main issue is the DataChangeManager and its in-ability to release locks on elements that are no-longer used inside the application.
Let me take a step back. In DCAF there is a DataChangeManager. This is a singleton that you can register with to receive notifications of changes to a specific class or instance of a BaseBO.
Now in some applications an instance of a BaseBO registers itself as a listener to itself.. Why would u do this? I hear you ask.. In a distributed system where there are multiple VM’s modifying similar data, its useful to be notified of these changes and reload the data accordingly. In conjunction with a DataChangedTransport using something like JMS this is a simple solution.
So now you know the situation, what is the issue. The problem is that the DataChangeManager has a fixed reference to the BO, and if that BO is no longer used by the application the Garbage collector should release it. But as the DataChangeManager is static, and has a reference to this BO the GC is still considers the element reference, even tho technically it isn’t going to be used by the application again. So we get a memory leak.
For a webapp I was working on, we had the User entity listening to itself for changes, and the entity was in a HttpSession. So while the session was active, the User was valid and being used within the application. Changes on a remote VM were propagated across, the User was notified and the contents reloaded. All working nicely.
But then the session is not interacted with for a while (the user closes the browser) and so the session timeout. The servlet container disposes the session and unlinks the User from it, so its no longer used, and we would assume its valid to be GC’d. But in the background the DataChangeManager still retains a reference and so the User lives on.
Without boring you on the details of how the GC works (you can read that anywhere) I’ll just cover the bits relevant here. Basically an object can be GC’d when it is not longer referenced by any valid threads or static instance.
In the previous example, User is referenced via the static DataChangeManager instance and so is not GC’able.
Now to the solution.
What needs to happen is to trick the GC into believing that the reference from the DataChangeManager to the User does not exist, so once all other reference are removed, the User is seen to be GC’able.
This sort of reference is called a “Weak Reference”. From my very quick and limited search through the current Java API’s there is a data structure that stores some data using Weak References, and this is a WeakHashMap.
The keys stored in this map are Weak References, and so not considered by the GC when it is time to work out what object can be GC’d.
So the change, was to update the internals of the DataChangeManager to store the references to the DataChangeListeners in a WeakHashMap instead of a List.
So there, hope that shows off another feature of the Java system that you may not have been too sure about. Please feel free to comment about this approach here, and if you want to try it out for yourself then head over to the development site to pickup a version of DCAF . These changes will be in the 1.2 release of DCAF to be released in the next week or so.
While browsing around at freshmeat I noticed that the latest Linux Kernel was updated yesterday.
http://freshmeat.net/projects/linux/?branch_id=46339&release_id=199319
Why do I care about this release you ask? Well Sharkey and I have been playing with getting a 6.12 kernel compiled to get DVB support for his MythTV box, and as you can see from the freshmeat release there is a mention of DVB drivers.
Changes:
This release features a newly added TPM driver required for certain IBM Thinkpad models. Various driver updates were made for DVB, USB, networking, sound, and SATA. The CIFS, JFS, and XFS filesystems have been incorporated. Extended support for AMD/Intel dual core CPUs and SuperHyway Bus has been added. IPv6 support has been declared stable. SELinux and software suspend have both been improved. The device mapper now supports multipathing. Address space randomization has been implemented.
Tonight was the Girls netball final, and the team “I think I can” ran out resounding winners. Not sure of the final score, but it was something like 23–14 or something like that.
It was a very different game to their usual style of play. Not sure if it was nerves, or that the chicks they played against were speeding the game up, but the usual confident game broke down a few times. That said, they never looked out of control of the game. They got the first 3 or 4 goals before the opposition scored and lead from there.
Having an extra player gave Rach a break in the first half, with the Purcells up front, Priscilla in the centre with the wings being controlled by Katherine and Jacinta. The usual suspects, Gaynor and Sarah, did their job of being the launching block of all the offensive moves by totally controlling defence.
As usual the umpires were involved in the game too much, they must be aspiring to be AFL umpires or something. They decided it would be a good idea to reset the scoreboard 1 minute into the 2nd quarter, thus losing track of the score and time. After a brief break the game got back underway with the score on 13–4.
At half time they were in total control, being something like 18–8.
After the half the team shuffled around a bit, Rach got her run as Priscilla sat out, but Gaynor was sent off to get a bandaid and so Priscilla made her return. The 3rd quarter saw the intensity of the oppositions defence lift, and I don’t think Anita touched the ball during that quarter. A goal or 2 to Jacinta steadied the ship but the opposition had fought back to a position of attack. The total dominance of the team was restricted as the general of the defence was off the field with the blood rule. With her return in the final quarter the team had its balance back and played out the quarter to achieve a great victory.
After being a new team who hadn’t played recently and not performing so well during the pre-season, the team really found its feet as the season progressed as they all worked out how to play together, finishing well on top of the ladder and going through the finals unchallenged to take the top prize.
Well done girls, lets just see where they re-grade you to next season.
Been a while since the last post, things are hectic at work as we are pushing towards getting the new stuff out the door so this post aims at recapping all the stuff thats been happening.
Went for a ride with Sharkey yesterday, did our big eltham circut, which head from my place up to the eastern freeway, along that east till we get to springvale rd then up along springvale rd till it ends. There is then a trail (the yarra creek trail I think) that winds its way west underneath eltham and all the way up to burke rd. The trail then turns south and links back up with our normal trail along the eastern which we then take back east to my place. Its about a 45km trip, which we did in just under 3 hours. We did stop a couple of times to watch some local footy and hockey so would probably be 2.5 hrs if we hadn’t stopped.
It was a much more serious ride than we have been doing recently, but the type of thing that we should be doing all the time. Once we got over the initial 10k mark the body had warmed up and it got easier from there. Only the last 5k which is up and down was a bit hard, but I'd hope that it was after 40k or we should be riding further.
So what else is going on.. Crickscore is back. I had an issue with the database corrupting and had to get help from the guy that built the database software to fix the errors. So a big thanks to Toby and his Mckoi database.
Given that Cooltools is on a break this season it wasn’t super important to get Crickscore back, but now it is it must be time to do some serious interface work. We’ll see how time goes over the next few weeks.
Downloaded KnoppMyth to try it out. Was ok, couldn’t get the Australian channels to load but the install was pretty painless.. Good to see development making this sort of technology more like an appliance. Now all I need is a machine capable of running MythTV happily and I'll be happy.
After playing with KnoppMyth, by torrent download of Fedora Core 4 (FC4) was complete, so decided to install that on my test machine. Yeah its nice. Got the latest firefox pre-installed and Gnome looks really cool.. I’ve been a kde guy for a long time, but on this install left Gnome as the default. I really like the menu bar and task bar separation. And the UI-themeing looks really clean.
The only problem with FC4 is that is so new that the apt-get repository's haven't been updated yet, to even a point that the apt-get rpm from freshrpms.net hasn’t even been build. But I can wait.
I’m planning on updating my main server, the one u got this from, from an older Redhat 9 release to the latest FC4. Just need to plan a backup first, just in case.
So what else has been going on??? Went and saw the Bahrs last night. Good to catch up with them again, its been a while since we have. Jessica (the latest to the clan) is so small and cute and Rach looked right at home with a new baby in her arms…
Not much else, and I think thats probably enough for now. I’ll try and get back soon with more details.
Oh, one last thing is that I'm working on a new whitesquare software development site. Thinking of using a blog engine to distribute news about all of the whitesquare products.. The current trial is over at dev.whitesquaresoft.com and I hope to get some content and the current beta downloads up in the next few days.
C ya!
Headed over to Sharkeys this morning for a bit of a spin to Jells Park. It was a great day for riding, except for the wind, and it seems we weren't the only people with the idea.
We passed more people on the trail today than we usually would in an entire month. Lots of friendly and happy hellos as we passed people on bikes, with dog, running or just out for a stroll.
We decided to not do the entire Jells Park trip, as I had to get home and get lunch organised. So it was only 22.13km for the trip, but with the head wind on the way back, we felt the ride.
As this site will show, its been a while since the last ride, so was good to just get out and about again. This arvo the Pies play Melbourne for the annual Queens Birthday clash, so now its time to fire up the BBQ, get the radio on and hope the boys can make it 4 in a row.
I ripped out a game I had lying around and chucked it on again. I forgot how much fun Empire Earth (EE) could be, and also that I hadn’t given it nearly enough of my time.
I am a huge fan of RTS games, but havn’t played through many since the serious time wasting days of Red Alert and Command and Conquer.
On the old machine EE played a bit slow, at a low res and was probably the reason that it went back on the shelf. But today was its time to be re-born.
On the new pc with tones of processor and ram the game runs perfectly, at the top resolution with all options on. From what I saw yesterday, the game is massive. There are 10–13 age’s to navigate thought, starting off in the Prehistoric age going all the way through to the Nanotech age.
I decided to explore the tech hierarchy by playing a skirmish game against the computer, but it took nearly 4 hrs to get through the first 3 ages.. The requirements to do the upgrade a huge and the time to collect the resources are long so it extends the game. That said, it makes you have to balance your civ.. Do we spend all resources becoming a technological master, or invest in a solid army to cut down and destroy the opposition?
Initial impressions, after playing for about 1/2 a day, is that it seems to have a great balance and upgrade structure. I hope to get this on the list of games to play at the next sharkeyLan.
Rach and I headed out after a yummy dinner of Pasta to the movies. Rach wanted to see the chick flick Mr and Mrs Smith. How is this a chick flick I hear you ask? All the guns, knives and explosions.. I’ll say just two words.. Brad and Angelina..
Onto the movie, it is again a very plot-less movie. A couple who are both hitmen don’t know that about each other. They then find out that they are each others target but are torn between their job and their partner.
Good for bangs and explosions. Brand and Angelina basically have 90% of the show time, so its good eyecandy. Its a movie that you won’t fall asleep in, but also not a lot of substance.
Not one i’d buy on DVD, but be happy to sit through and watch again.
After a few weeks of discussion, we decided to bite the bullet and invest in a manual pasta maker. So this afternoon we played around and made a couple of batches.. The actual pasta is simple, flour and egg.. Thats it.
Then run it through the machine a few times to combine it, then flatten it to the required thickness and either cut it manually or use the provided cutter to make spaghetti or fettucini.
Yummy..
Tonight the plan is to make another batch for dinner and work on a from-scratch bolognese sauce.
Went to see the Hitchhikers Guide to the Galaxy with Matthew. The plan was to go and watch Star Wars, but he had already seen that, and Rach was going to her mums..
Seeing as the movie was about to finish its run, we decided to head to Forest Hill and see one of the remaining screenings.. We got to the 9:40 screening, and were 2 of 13 people in the cinema to watch it.
Not being a big fan of that world, I expected the movie to not be that great, and all though there is basically no plot to the movie, it was very entertaining and had some seriously funny scenes.
If u havn’t seen it, and have a slight interest in the sci-fi world, then I’d recommend checking it out. I’m not sure how it stacks up to the book as I've never read it, but it was entertaining all the same.
Test 2 with a new account via BlogJet….
I’ve just got the latest BlogJet beta. I logged an issue that images were missing a slash (/) when posting embedded images. This meant that I had to re-download the post and manually edit the html to add the slashed back in.
But hopefully this has been fixed in the new release of BlogJet, so now I'm testing to see if the fix has worked..
I had to find an image to post, and this was something I had lying around… so lets see…
1…. 2….. 3…. publish.
Update: As you can see the image is still broken.. I’ll leave it broken incase the BlogJet developers want to see a live posting with the image broken.. It’s pretty easy to explain, but at least here is an example.
Its now been 2 days since Collingwoods win in round 11 and I’m sure that I’m not the only one whos still talking about the win and happy to see the boys not only winning, but playing great football.
As it was a Pies home game I was there, but the story surrounding the night is a bit more complex than usual. This week we played the Cats on Friday night at the Telstra Dome. Gaynor is a Cats member and decided to organise a group of Cats and Pies people to go watch the game together. So there were a heap organised to go. Puss, Anita, Dave, Nicola, Gaynor and Me, along with a couple of others from Gaynors work.
But in the process of planning Friday night, Puss found out that the game was a sellout and we all wouldn’t be able to go.. But as Gaynor and I were members we should have been able to get in as long as we were there early enough to get a seat.
So the plan was for Gaynor and I to meet at about 5:30 and find a seat somewhere.
That all changed when I got a call from work and Kate said that there were 3 Medallion Club tickets available for the game if I was interested.. Was I interested… of course I was.. So I picked up the tickets from Scott in the city and he told me that they were the best seats in the place.. I wasn’t too sure about that but when I got there and met up with Gaynor we soon saw that they were.
Level 2 seats 52 and 53 in Row A, asile 13.. Thats front row, level 2 directly on the wing. I’ve got some photos, but there from my phone so not sure how good they will be. I also can’t put them up here yet as I don’t have the IR cable for the phone, but i’ll post them soon.
Anywho, onto the game.. And what a great game it was.. We kicked away early and it was only a late charge in the first quarter that made it look a lot closer than it really was.
But it was the second quarter that we opened up kicking 6.4 to geelongs 1.2. So in for a beer at 1/2 time feeling great sitting on a 7 goal lead.
As expected the Cats came out hard after the long break and clawed the gap back to 5 goals heading into the final quarter, and all tho the cats did win the final quarter by a goal we still ran out victors by 4 goals.
A great game, well played by Didak kicking 5 straight and really opening up the forward line. So now we wait till the Queens Birthday game against Melbourne next Monday. Lets hope we can make it 4 in a row.
Ok, so thats a bit dramatic, but I was a key in our loss. I’ll start from the start. Last night I played my first game of soccer with the boys this season, so its been 4–5 weeks since the last run.
I was feeling pretty good, no aches or pains and expected to run out a good game. The game started at 6:00 and most of us were there by about 5:30. We had a good run around b4 the game and got nice and warm (a bit much possibly).
I started on the bench for the first half and we looked ok, they had a fillin guy who was waaaay to good, but that was ok as their other players were on a par standard with us. We played well but had a few goals scored on us (4) in the first half. I can say that at least 2 were probably my fault. This is where I get the disaster idea from…
I got caught so many times either standing still and letting them or the ball just sail by me, not chasing or putting any pressure on them.. No real excuse but slack..
So I tried to learn from that and put some effort into tagging/manning up someone at all times in the second half, and I thought my game improved due to that fact..
Also my forward/attacker role is in serious need of work.. How many times did Kev get the ball out of goals to me on my own for me to just miss it and stuff up..
Anywho, we did kick 2 goals to 1 in the second half to give us a 5–3 loss.. Not too bad, but lots of room for improvement. We’ll see when the next game I play if I listen to my own advice..