You said you use SPARC Solaris for your school, where do you go? I'm at Kutztown University in PA and it sounds just like the setup we have here. I'm supposed to be hacking some LISP and ADA for class right now, but I'm working on the box I promised myself I'd have done by the time this semester started (4 weeks ago). I know how it goes:). Give Slackware-12 a shot, if you use Solaris over SSH for your school work, you'll feel right at home. And Solaris sometimes blows up while being patched in my few weeks of Solaris Administration experience.
Yeah, I deserved OT, I'll give the mods that one. I got karma to burn anyways and it's always worth it for a good discussion (that's why were here, right?).:)
I, personally, didn't like Solaris on the whole; it's conceptually great, but it's like baby sitting a 5 year old. It whines, won't tell you what it wants all the while refusing to do what you ask of it. It seems that Sun has Not Invented Here Syndrome so much worse than even Red Hat, in much the same way. It's like whenever you want to do something, you have to find out what they have named their implementation of something everyone else uses, then find out the appropriate interface to use. I run Slackware (which, if you aren't familiar with, has been described as 'pure vanilla Unix'), and I'm so used to just going straight to a config file. This puts me at odds with Solaris' philosophy which I think is, "don't worry about how its done, we'll take care of it for you, so long as you don't mind the learning curve that's the same as if we weren't handling things behind the scenes. So, I'm extremely bias in my opinion and I really didn't give it a really fair shot. It had ticked me off from install where I could use my graphics card to install the OS, but on reboot it would crash trying to use this very same card.
At work I have to run RHEL to keep my boss comfortable, and I don't like it for the fact that they constantly build their own interfaces to configurations - but you don't have to use them. Solaris actually stamps the top of their configuration files "DO NOT EDIT THIS BY HAND!"; they don't tell you the appropriate interface to use, they just tell you not to edit it manually. If their custom scripts and such can't parse a config file with all of the user land applications in *nix (although all of theirs are somewhat lacking in functionality - don't bother trying to compress with tar, it can't do it), I'm just not sure how much confidence I have in their product. But, like I said, Solaris and I got off to a bad start which skews my opinion.
I'd say give it a shot. They really do have great documentation online (entire libraries) if you don't mind sifting through it all. ZFS is awesome (I got it running fine once I could get SSH going, a graphics card later), and their community is fairly active and agreeable, IMHO. I just feel like it's Unix, but with all the bells and whistles that someone else decided they would like in their own distro, instead of a toolbox of open-ended applications wrapped up and ready to be customized by you. For me, that works against the beauty of *nix which is simplicity and portability. If you like RHEL or SLED, you might feel very comfortable with Solaris. If you like debian based distros, or working from a command line, you'll probably hate it. If you like BSD, you'll probably be indifferent.
I don't know about Sun... I've run OpenSolaris this summer for ZFS (which, BTW absolutely rocks!), and it felt like baby sitting a 4 year old. However, Sun does sell awesome hardware/OS packages (albeit very expensive) and really does have a nice modular enterprise software stack. I think they'll end up becoming an IBM, grow old and respected community member making good revenue consulting and doing high end systems. Then again, they are still holding their own with Java and netbeans (ironically, IBM's eclipse community is looking to netbeans as a desired direction for GUI design), so I wouldn't count them off the desktop any time too soon. BTW, it just hit me, whatever happened to JavaFX?
Doing this job well? Always!
on
Ethics In IT
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· Score: 2, Interesting
Actually, I've been at the place for 3 years (1 year full time while I took 2 semesters off from school to get my head straight), and I can easily say that it was worth it.
I spent a year of straight "heads down" time, doing network administration, database administration (we use Access 2000, but it's exposure nonetheless), writing a backup tool (and porting it 3 times "...it's only temporary, you know." - yeah, right), and learning RHEL during the day. At night I was writing a win32 application, bash scripts, C/C++ code, Java, playing with advanced routing, samba, and kernels in Slackware Linux, and constantly digging in to technical documentation and CS theory. The time has paid off ten fold. The difference between myself and my peers without 'hand-on' experience is simply astounding!
I didn't realize until I took graduate level administration and programming classes last semester and this semester and I breezed through them without cracking a book. My code is cleaner, better documented, and formatted better than when I was taking AP C++ in high school. I look at applications (regardless of platform - I'm running 3 flavors of Linux, a Mac and a Windows box at home, a RHEL box at work, and work on a Solaris box at school) in a completely different way than ever before. I don't see an application any more, but rather layers of abstraction connected via interfaces.
Once I realized that everything is a connecting interface from the backend to the frontend (protocols, devices, GUIs, etc., everything), I found I could do incredibly complex things in both programming and administration - it's just about getting the right interfaces on the right layers. It was a moment of revelation that compares to when I found out in *nix, everything is a file. The light went on! I also found out that C/C++ is almost a completely different language on each platform. GNU, win32, xcode might as well be 3 separate languages. Good documentation is worth its weight in gold. Version control is How It Should Be. And, every bit of knowledge is a tool in your toolbox; the more tools at your disposal, the more elegant your solution and the less forehead dents in your desk. Finally, if your interface layers are concise all the way up, everything falls in to place all the way up to the GUI and troubleshooting and bug fixing become single line fixes instead of full function kludges. That being said, I still write a lot of crap code... but at least I know when I'm doing it now.
Sorry for that rant, but I really had to comment on what the job has taught me.
Re:ethics require education
on
Ethics In IT
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· Score: 1
To be honest, I always figured that everyone would just do it (I'm in college - this is my "intern" position and my first glimpse of the business world) without me having to be an enforcer - I'm a software development major, not a network administration, IT, or straight CS major. I don't have a very strong liking for administrators who use technical means to enforce something where "...hey could do this for me..." would suffice. If someone told me that I was given an insecure password, that would be motivation enough to change it ASAP.
Also, I usually have to do a bit of prep work to an account depending on what the person will be doing (the default profile just doesn't cover all my use cases), so it usually gets a good 3 or 4 logins before being handed to the user. I spoke with my boss about 30 day max length on passwords, but that went over like a lead zeppelin.
Re:ethics require education
on
Ethics In IT
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· Score: 1
When I first create a user account at work, the password is the username. I have told at the very least 5 people "your password is the username I just gave you, as soon as you login, hit ctrl+alt+del and click on change password. Don't tell me what it is, and don't share it, we have public usernames if anyone without an account needs to jump online or something." Not a single person has changed their default password.
Ladies and gentlemen, this is an unparalleled breakthrough in cotton candy technology. Will it keep it from sticking to my fingers, which I then lick, which leads to stickier fingers, which I lick again?
It's not a function of stupidity, it's a function of the limited fanout factor of a computer. The brain has a fanout factor of 10,000 whereas a computer has a fanout factor of 10, IIRC. Our mind can grasp details, isolate them and compare them to other 'things' (experiences, objects, people, sights, sounds, etc.) without explicit instructions to do so, whereas a computer cannot (and I highly doubt ever will) do this. This is as I understand it from talking to someone, somewhere down the line - please correct me if I'm off base.
Dude, for me to run through every option to compile a kernel on my somewhat esoteric hardware at work takes maybe an hour... and most of that time is looking up specs on my hardware.
You'll not be running anything under Xen or VMWare without extra modules (RHEL 5.1 ships with a Xen upstream kernel now). As for Samba, I hope you don't want ACL support; you'll need a kernel compile for that - Extended Attributes aren't enabled by default. If you need the newest e1000 driver on your integrated NICs, you can add it in yourself or wait for your provider to support it.
I'm just saying there are legit reasons for hand compiling a kernel. Sorry, I've had this discussion before and it's a bit of a sore point for me. Binary kernels are all well and good for a good majority of cases, but some times you need specific kernel operations or abilities that are not going to be supplied and supported by your upstream provider. Then again, I'm used to being my own upstream provider from running Slackware... maybe I'm just not looking at it from the right perspective.
OT, but I couldn't find on your site (and your username doesn't have any contact info)... do you have any plans for data warehousing? I've got about 40GB that I'm rsyncing (the daily diff is usually a few meg, a few hundred when we dump images from our product pics) around, but I'd like a place to shove it offsite. It seems that the only plans available to meet my needs are dedicated root servers - just so I can run rsyncd. I'm not going to host a site from the thing. What would you suggest for an offsite simple backbone/service/raid box (besides the one I have at home - my ISP doesn't like services on the wire, and they're the only game in town if they cancel my subscription)?
What do you think they're building all those shiny new datacenters for? Heating? When I need to warm up my apartment, I just pull a 500Gb drive for a moment and then put it back in and warm up while my RAID 5 rebuilds.:P
Yeah, but I think in Linux all you have to do is pull the microcode update support from your kernel (during a 'make menuconfig') and Intel can't update your CPU. I don't think AMD even has the ability to update the microcode. That and it'll probably take a reboot to enable the new code (complete assumption on my part), couldn't you do something to the effect of running tripwire on/dev/cpu to be notified of changes?
Surely they have a mechanism to roll back code updates, it would be borderline insane if they didn't... so, you've got the code (wireshark, tcpdump), the key (embedded in CPU), and the mechanism (kernel support code) - are you implying that this isn't enough to reverse engineer any/or revert microcode changes? I don't know the first thing about it, but this should be reversible for the same reason that DRM doesn't work - they have to give you the ability and the key if they want to run it on your machine.
I know this was like 2 months ago, but I just got to reading it... I salute you! That made my frickin' night, maybe even week. Rock on! BTW, hit me, I need the money!
I saw an article a year or two ago (Wired, IIRC) that postulated that if you solved AIDS worldwide, you'd have just as many deaths from starvation due to overpopulation. If only it were as simple as solving AIDS, which is, in and of itself, an incredibly hard problem...
My school has a subscription to Ruckus; it's free to use with a student email address and is supported by advertising in their proprietary player. It's DRM'ed and all that, but with a firefox search bar plugin and cookies keeping me logged in, I have music at my fingertips within a few seconds of having an urge to hear it. The download goes straight to the player (which is really a skinned WMP, with an ad bar at top and bottom) and is added to my play list.
The problem is that, mostly, whatever I download is rocketed to the recycle bin within a few plays. Most of what's popular is crap at best. Although, I have found a few bands that have become permanent parts of my collection that I wouldn't have given a spin if I had to pay. If I get "you gotta' hear this band!" from a friend with decent taste, I can download it without shelling out cash I don't have (hrm... books or food this semester... knockoff books from over seas and generic brand ramen, FTW!), for a disc that would end up as a coaster anyways. I'm not a fan of DRM, but if I like the music I end up buying it anyways. Unfortunately, they only have a player for Windows, so my G3 and Linux boxes are lacking support.
So what about public boards where a spider can pick up your email address? That being said, this is a really good idea; do you have it automated at all? For instance, do you have a catch all that is white listed so long as the incoming email address isn't black listed? Or do you manually add a white list entry for each new email?
No doubt as to all your points, I run Slackware where it matters... It Just Works. However, the proprietary world can't afford to look stupid; they've got to prove themselves. The rest of us (Apple servers included, even though they're somewhat proprietary, although BSD derived) don't have anything to prove - our uptime does the talking. A microsoft box with a high uptime is either an unpatched disaster waiting to happen, or a honeypot.
However, I think that you write off Microsofts ability to shoot themselves in the foot when it comes to "too late to rewrite"; they'll come to the same conclusion and then try to carry over the parts of the code base that they think kinda' work (smb, anyone? It's come to the point where they're afraid to touch that subsystem!), kill any non-essential feature and then get it mostly right by service pack 2 or 4, by which time they'll be in extended support.
I work alone on projects (I'm a software development student), I rarely have full blown branches or full blown versions (I use a major.minor.fix notation where odd minors are unstable, but I don't have a roadmap as to what version number has which features). While I use git somewhat (read: with a man page on term. 2) when reading kernel code or for kernel hacking, I'd never use it for my school or work projects; I use svn for them, and not even with all its features (barely any tagging, branching, merging). Basically, I just want a place to commit my code that integrates in to whatever IDE I may be using at that time, as I work with 5 or 6 languages at any given time. It needs to backup easily, and stay out of my way otherwise. Diff output is icing on the cake. If I take a wrong turn somewhere, I can revert to a previous commit or apply a diff against one commit from another, and I have annotations for each commit so that when I go back a few months later and ask, "what in the world was I doing this for?", I can just read the commit annotations.
Git, while cool, provides me nothing in the way of features I need at the cost of a somewhat steep learning curve. It's just not the tool for my current job. I need a light duty hammer that fits my tool belt. Git is the belt fed, compressed air, master carpenters nail gun; it's really, really cool, but is entirely overkill for my needs and does not fit my tool belt at all. Furthermore, it comes with a heavy manual that I'd better read if I'd like to keep all my fingers!
To summarize, every tool has a problem it's supposed to solve, otherwise it has no reason to be invented, if a given tool is not fixing my problem, then it does me no good.
EEk! As I was reading your reply, I remembered how Microsoft played off the hotmail thing as how great their new server platform was (2K, IIRC), when in fact it was a disaster. The fact that they pulled it off is really just showing that they have good people in their upper tech tier who only come out when they need the Big Guns, IMHO.
Anyways, who thinks that Yahoo is going to be a testbed for the next Microsoft Server platform? Longhorn, I believe - I don't follow Microsofts technologies too closely since there are too many, and only half of them seem to make it to production... the rest are broken up, renamed and reimplemented in a way that you're not really sure which application is a subset of which application or where it integrates. They get to test out a wide scale deployment without wrecking their own infrastructure, and as a side bonus, these things never go smoothly anyways, so no one will really think too much of it. Maybe I'm just paranoid, but if they haven't thought of this, I'd have to wonder why not - I probably would in their position.
My problem with multitasking is the overhead associated with calculating what has to be started when, how long it will take, etc... I think it's this overhead that breaks up the flow in my concentration. Flow, however, is also related to how difficult a task is for you; if you have a more innate sense for calculating schedules, it will probably break up your flow less. Also, for me, the problem is when I multitask and several tasks end almost at the same time and I have to batch out a new series of tasks; afterwards I always have to swap back in what I was working on when I got interrupted and had to figure out how to lay out new tasks. I think this is where flow breaks down the most.
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You said you use SPARC Solaris for your school, where do you go? I'm at Kutztown University in PA and it sounds just like the setup we have here. I'm supposed to be hacking some LISP and ADA for class right now, but I'm working on the box I promised myself I'd have done by the time this semester started (4 weeks ago). I know how it goes :). Give Slackware-12 a shot, if you use Solaris over SSH for your school work, you'll feel right at home. And Solaris sometimes blows up while being patched in my few weeks of Solaris Administration experience.
I, personally, didn't like Solaris on the whole; it's conceptually great, but it's like baby sitting a 5 year old. It whines, won't tell you what it wants all the while refusing to do what you ask of it. It seems that Sun has Not Invented Here Syndrome so much worse than even Red Hat, in much the same way. It's like whenever you want to do something, you have to find out what they have named their implementation of something everyone else uses, then find out the appropriate interface to use. I run Slackware (which, if you aren't familiar with, has been described as 'pure vanilla Unix'), and I'm so used to just going straight to a config file. This puts me at odds with Solaris' philosophy which I think is, "don't worry about how its done, we'll take care of it for you, so long as you don't mind the learning curve that's the same as if we weren't handling things behind the scenes. So, I'm extremely bias in my opinion and I really didn't give it a really fair shot. It had ticked me off from install where I could use my graphics card to install the OS, but on reboot it would crash trying to use this very same card.
At work I have to run RHEL to keep my boss comfortable, and I don't like it for the fact that they constantly build their own interfaces to configurations - but you don't have to use them. Solaris actually stamps the top of their configuration files "DO NOT EDIT THIS BY HAND!"; they don't tell you the appropriate interface to use, they just tell you not to edit it manually. If their custom scripts and such can't parse a config file with all of the user land applications in *nix (although all of theirs are somewhat lacking in functionality - don't bother trying to compress with tar, it can't do it), I'm just not sure how much confidence I have in their product. But, like I said, Solaris and I got off to a bad start which skews my opinion.
I'd say give it a shot. They really do have great documentation online (entire libraries) if you don't mind sifting through it all. ZFS is awesome (I got it running fine once I could get SSH going, a graphics card later), and their community is fairly active and agreeable, IMHO. I just feel like it's Unix, but with all the bells and whistles that someone else decided they would like in their own distro, instead of a toolbox of open-ended applications wrapped up and ready to be customized by you. For me, that works against the beauty of *nix which is simplicity and portability. If you like RHEL or SLED, you might feel very comfortable with Solaris. If you like debian based distros, or working from a command line, you'll probably hate it. If you like BSD, you'll probably be indifferent.
I don't know about Sun... I've run OpenSolaris this summer for ZFS (which, BTW absolutely rocks!), and it felt like baby sitting a 4 year old. However, Sun does sell awesome hardware/OS packages (albeit very expensive) and really does have a nice modular enterprise software stack. I think they'll end up becoming an IBM, grow old and respected community member making good revenue consulting and doing high end systems. Then again, they are still holding their own with Java and netbeans (ironically, IBM's eclipse community is looking to netbeans as a desired direction for GUI design), so I wouldn't count them off the desktop any time too soon. BTW, it just hit me, whatever happened to JavaFX?
I spent a year of straight "heads down" time, doing network administration, database administration (we use Access 2000, but it's exposure nonetheless), writing a backup tool (and porting it 3 times "...it's only temporary, you know." - yeah, right), and learning RHEL during the day. At night I was writing a win32 application, bash scripts, C/C++ code, Java, playing with advanced routing, samba, and kernels in Slackware Linux, and constantly digging in to technical documentation and CS theory. The time has paid off ten fold. The difference between myself and my peers without 'hand-on' experience is simply astounding!
I didn't realize until I took graduate level administration and programming classes last semester and this semester and I breezed through them without cracking a book. My code is cleaner, better documented, and formatted better than when I was taking AP C++ in high school. I look at applications (regardless of platform - I'm running 3 flavors of Linux, a Mac and a Windows box at home, a RHEL box at work, and work on a Solaris box at school) in a completely different way than ever before. I don't see an application any more, but rather layers of abstraction connected via interfaces.
Once I realized that everything is a connecting interface from the backend to the frontend (protocols, devices, GUIs, etc., everything), I found I could do incredibly complex things in both programming and administration - it's just about getting the right interfaces on the right layers. It was a moment of revelation that compares to when I found out in *nix, everything is a file. The light went on! I also found out that C/C++ is almost a completely different language on each platform. GNU, win32, xcode might as well be 3 separate languages. Good documentation is worth its weight in gold. Version control is How It Should Be. And, every bit of knowledge is a tool in your toolbox; the more tools at your disposal, the more elegant your solution and the less forehead dents in your desk. Finally, if your interface layers are concise all the way up, everything falls in to place all the way up to the GUI and troubleshooting and bug fixing become single line fixes instead of full function kludges. That being said, I still write a lot of crap code... but at least I know when I'm doing it now.
Sorry for that rant, but I really had to comment on what the job has taught me.
Also, I usually have to do a bit of prep work to an account depending on what the person will be doing (the default profile just doesn't cover all my use cases), so it usually gets a good 3 or 4 logins before being handed to the user. I spoke with my boss about 30 day max length on passwords, but that went over like a lead zeppelin.
When I first create a user account at work, the password is the username. I have told at the very least 5 people "your password is the username I just gave you, as soon as you login, hit ctrl+alt+del and click on change password. Don't tell me what it is, and don't share it, we have public usernames if anyone without an account needs to jump online or something." Not a single person has changed their default password.
Ladies and gentlemen, this is an unparalleled breakthrough in cotton candy technology. Will it keep it from sticking to my fingers, which I then lick, which leads to stickier fingers, which I lick again?
For the record, you're allowed to have a *dominant* one, just like being right handed... I happen to be right nutted.
You'd better laugh; I'm going to lose a job interview some day over this post when they ask me what tech. sites I frequent!
It's not a function of stupidity, it's a function of the limited fanout factor of a computer. The brain has a fanout factor of 10,000 whereas a computer has a fanout factor of 10, IIRC. Our mind can grasp details, isolate them and compare them to other 'things' (experiences, objects, people, sights, sounds, etc.) without explicit instructions to do so, whereas a computer cannot (and I highly doubt ever will) do this. This is as I understand it from talking to someone, somewhere down the line - please correct me if I'm off base.
You'll not be running anything under Xen or VMWare without extra modules (RHEL 5.1 ships with a Xen upstream kernel now). As for Samba, I hope you don't want ACL support; you'll need a kernel compile for that - Extended Attributes aren't enabled by default. If you need the newest e1000 driver on your integrated NICs, you can add it in yourself or wait for your provider to support it.
I'm just saying there are legit reasons for hand compiling a kernel. Sorry, I've had this discussion before and it's a bit of a sore point for me. Binary kernels are all well and good for a good majority of cases, but some times you need specific kernel operations or abilities that are not going to be supplied and supported by your upstream provider. Then again, I'm used to being my own upstream provider from running Slackware... maybe I'm just not looking at it from the right perspective.
You just NAILED it! Extra props for the system design analogy... any chance that next time you can use system design/car analogy? :)
OT, but I couldn't find on your site (and your username doesn't have any contact info)... do you have any plans for data warehousing? I've got about 40GB that I'm rsyncing (the daily diff is usually a few meg, a few hundred when we dump images from our product pics) around, but I'd like a place to shove it offsite. It seems that the only plans available to meet my needs are dedicated root servers - just so I can run rsyncd. I'm not going to host a site from the thing. What would you suggest for an offsite simple backbone/service/raid box (besides the one I have at home - my ISP doesn't like services on the wire, and they're the only game in town if they cancel my subscription)?
What do you think they're building all those shiny new datacenters for? Heating? When I need to warm up my apartment, I just pull a 500Gb drive for a moment and then put it back in and warm up while my RAID 5 rebuilds.
Surely they have a mechanism to roll back code updates, it would be borderline insane if they didn't... so, you've got the code (wireshark, tcpdump), the key (embedded in CPU), and the mechanism (kernel support code) - are you implying that this isn't enough to reverse engineer any/or revert microcode changes? I don't know the first thing about it, but this should be reversible for the same reason that DRM doesn't work - they have to give you the ability and the key if they want to run it on your machine.
Please correct me if I'm wrong.
I know this was like 2 months ago, but I just got to reading it... I salute you! That made my frickin' night, maybe even week. Rock on! BTW, hit me, I need the money!
I saw an article a year or two ago (Wired, IIRC) that postulated that if you solved AIDS worldwide, you'd have just as many deaths from starvation due to overpopulation. If only it were as simple as solving AIDS, which is, in and of itself, an incredibly hard problem...
The problem is that, mostly, whatever I download is rocketed to the recycle bin within a few plays. Most of what's popular is crap at best. Although, I have found a few bands that have become permanent parts of my collection that I wouldn't have given a spin if I had to pay. If I get "you gotta' hear this band!" from a friend with decent taste, I can download it without shelling out cash I don't have (hrm... books or food this semester... knockoff books from over seas and generic brand ramen, FTW!), for a disc that would end up as a coaster anyways. I'm not a fan of DRM, but if I like the music I end up buying it anyways. Unfortunately, they only have a player for Windows, so my G3 and Linux boxes are lacking support.
So what about public boards where a spider can pick up your email address? That being said, this is a really good idea; do you have it automated at all? For instance, do you have a catch all that is white listed so long as the incoming email address isn't black listed? Or do you manually add a white list entry for each new email?
However, I think that you write off Microsofts ability to shoot themselves in the foot when it comes to "too late to rewrite"; they'll come to the same conclusion and then try to carry over the parts of the code base that they think kinda' work (smb, anyone? It's come to the point where they're afraid to touch that subsystem!), kill any non-essential feature and then get it mostly right by service pack 2 or 4, by which time they'll be in extended support.
Git, while cool, provides me nothing in the way of features I need at the cost of a somewhat steep learning curve. It's just not the tool for my current job. I need a light duty hammer that fits my tool belt. Git is the belt fed, compressed air, master carpenters nail gun; it's really, really cool, but is entirely overkill for my needs and does not fit my tool belt at all. Furthermore, it comes with a heavy manual that I'd better read if I'd like to keep all my fingers!
To summarize, every tool has a problem it's supposed to solve, otherwise it has no reason to be invented, if a given tool is not fixing my problem, then it does me no good.
Anyways, who thinks that Yahoo is going to be a testbed for the next Microsoft Server platform? Longhorn, I believe - I don't follow Microsofts technologies too closely since there are too many, and only half of them seem to make it to production... the rest are broken up, renamed and reimplemented in a way that you're not really sure which application is a subset of which application or where it integrates. They get to test out a wide scale deployment without wrecking their own infrastructure, and as a side bonus, these things never go smoothly anyways, so no one will really think too much of it. Maybe I'm just paranoid, but if they haven't thought of this, I'd have to wonder why not - I probably would in their position.
I've met some people who really are tools! Fortunately, they're usually marketing.
My problem with multitasking is the overhead associated with calculating what has to be started when, how long it will take, etc... I think it's this overhead that breaks up the flow in my concentration. Flow, however, is also related to how difficult a task is for you; if you have a more innate sense for calculating schedules, it will probably break up your flow less. Also, for me, the problem is when I multitask and several tasks end almost at the same time and I have to batch out a new series of tasks; afterwards I always have to swap back in what I was working on when I got interrupted and had to figure out how to lay out new tasks. I think this is where flow breaks down the most.
Fortunately, the only winning move was not to play (tic-tac-toe!), and it all ended well!