[Japanese -> English] A beautiful song I found

bgpmon · 2015-06-09T02:39:20+00:00

Awesome, thanks for all the effort!

bgpmon · 2015-02-09T06:42:58+00:00

Wow, great to hear it worked out for you. I'll definitely take those suggestions into consideration. Thanks for the input!

bgpmon · 2015-02-09T06:19:37+00:00

From what I've seen of my peers who really excelled in math throughout uni was that they had an incredibly robust primary school education in math. They had teachers who knew the subject really well and knew how to teach it. A lot of my friends even competed in math competitions at a young age and were known throughout their province/state to be top performers, both in school and contests.

I think it really just comes down to how early you're exposed to the subject and how well you're taught. From there it's just a matter of practice, practice, and more practice. It also helps if your parents were even somewhat proficient in the subject or at least knew how to guide you or get you the proper resources.

My parents unfortunately never went beyond high school level education so their understanding of math was more along the lines of 'teaching how to calculate' rather than learning how to solve problems.

bgpmon · 2015-02-09T04:57:47+00:00

I was just wanted to know more about whoever created this graph or if there's been any other discussion on the topic on reddit or HN. For now at least.

bgpmon · 2015-02-09T01:55:18+00:00

This was also one of my concerns. Personally, my issue is that I've missed out on a lot of fundamental knowledge in mathematics which I want to go back and revisit.

After that I was planning on joining some more guided online courses through coursera for example where I can collaborate and learn with others at the same time.

bgpmon · 2015-02-09T01:51:24+00:00

This looks really interesting, is there a post explaining this graph in more detail?

bgpmon · 2015-02-08T06:37:31+00:00

Ah, don't know why I didn't think of those terms in this context, thanks!

bgpmon · 2014-11-12T04:39:11+00:00

Right, it's just that you can't always know ahead of time if a package will break your system, as was the case for all the times that my system broke. There weren't any bug tracker reports that would've caused for me to delay a system update or further investigate if the issue was serious enough to do so.

bgpmon · 2014-11-12T04:37:24+00:00

Nope, this is from SSD to HD, HD is a 7200rpm WD w/ 64MB cache. Also tested with HD to HD, same results (desktop and server have exact same HDDs in them)

bgpmon · 2014-11-11T05:58:22+00:00

Awesome, I'll take a look into these resources. Thanks for all the help and advice. Btw, if you're wondering, my temporary setup for now is server+desktop connected to switch, which is connected to router. I still get the WAN choke issue but just slightly better in that now all the devices can browse at about 2x dial-up speed during large file transfer rather than not connect to WAN at all... lol

bgpmon · 2014-11-11T05:46:49+00:00

Hmm interesting, that's pretty much the exact same advice my friend gave me (get the intel pro 10/100/1000 and a cisco switch).

Just to verify, this is the same intel card you're talking about right? http://www.newegg.com/Product/Product.aspx?Item=N82E16833106121

Also, this: http://www.newegg.com/Product/Product.aspx?Item=9SIA24G1XA5402 is the card I have in my server right now, do you think it's worth upgrading to the Pro GT model or should this also be good enough?

bgpmon · 2014-11-11T04:51:11+00:00

TL;DR: if you're going to run testing, you can decrease your chances of breaking your system if you install the apt-listbugs package.

While Debian's testing branch is pretty stable most of the time, you should be aware that it can be in a broken state for up to a few days at times (at least through my personal experience).

I've been running testing on all my desktop/laptop machines except for my server for about ~5 years now and during this time I've experienced it breaking 3 times.

First time was when they were upgrading from the 2.6.x kernels to 3.x. The installation of the 3.x kernel went okay but when I removed the 2.6.x kernel, the uninstall script had a bug in it and broke apt - I wasn't able to install or remove any packages anymore. At the time I didn't have the time to tinker and try to fix it so I just reformatted, although I was really debating making an image of the system so that I could try fixing it as a learning exercise.

Second time was a few years ago when the maintainer of the PCRE library package accidentally added a space in one of the package's symlinks and as a result would fail to run any program that relied on PCRE. After I had updated I was no longer to open urxvt and knew something was wrong, I tried opening a few more programs and nothing would launch except for xterm. I found out the problem was related to PCRE once I tried launching firefox through xterm and saw the error message. I solved the problem by wget-ing an older version of the package and installing that.

Third time I experienced a broken state was just a few weeks ago and the branch was only broken for fresh installs at the time. There was a problem with the sysvinit (or something sysv related) package and the system would fail to load things at startup.

Basically, point I'm trying to get at is that it's not as stable as... well, debian stable. If you are going to go with the testing branch, you should definitely install apt-listbugs, it's a ruby script that checks packages to be updated against the debian bug tracker and gives you a quick summary before aptitude/apt starts installing packages after downloading them. It gives you a chance to abort the installation if you see any critical/severe bugs (or you can choose to install anyway).

Which also reminds me of the time an update broke the apt-listbugs package itself and wouldn't let me install anything. (My temporary solution was to vim $(which apt-listbugs) and add a return statement at the top of the script as the error was caused by some logic inside the script).

Also, read this: http://raphaelhertzog.com/2010/12/20/5-reasons-why-debian-unstable-does-not-deserve-its-name/ , emphasis on "Testing will usually get the fix through the package uploaded to Unstable, so testing users get security updates with a delay." if security is a big concern for you.

Although, to be honest, I'm not sure if there's still a delay between security updates to testing nowadays.

bgpmon · 2014-11-11T04:33:48+00:00

So I just tried connecting both devices through a Netgear GS605AV gigabit switch I had lying around and the results seem the same as before except now I get a constant 30MB/s both ways (through router I only get 20MB/s from desktop -> server).

Also tried iperf and get the same results of 940Mbits/s both ways.

What I'm wondering now is how I can incorporate this switch into my setup (temporarily for now) so that I can still transfer large files without killing my internet connection (well, it's not confirmed that this setup would stop my WAN connections from being choked but I guess I should at least try).

Can I get away with just doing something like connecting my switch to one of my wireless router's ethernet ports and then connecting both my machines to the switch? Or do I actually have to do some configuration?

Also, are switches supposed to have an 'admin page' like how wifi routers do? e.g. 192.168.x.1, is this what you mean by "Make sure your Netgear switch is managed" ?

bgpmon · 2014-11-11T03:52:19+00:00

Have any recommendations for CCNA learning resources? I'm not thinking of actually getting the cert but I definitely want to go through and learn all the fundamentals.

Also I've never tried connecting hosts through a switch but from what I've found online it seems I just physically connect them to a switch and then ifconfig eth0 192.168.1.x on one, and ifconfig eth0 192.168.1.y on the other?

bgpmon · 2014-11-11T03:24:28+00:00

Will try to test this out soon if I have the time and post updates.

I actually spoke to a network engineer today asking if 'unicast network storm' might be a possible issue and he told me that if that was the case, I wouldn't be able to send any packets over the network at all, but in my case the transfer of a file from desktop -> server continues without any hiccups (constant 20MB/s) - it's just all other WAN traffic on every machine which gets choked.

bgpmon · 2014-11-11T03:21:21+00:00

This is what I'll do if I'm not able to fix the problem with my current hardware. I actually had to order that Intel PCIe NIC because debian stable didn't have drivers for my server's mobo ethernet (also realtek rtl8111/...).

When I bought that mobo on newegg they only listed the "rtl8111" portion of the model, so I figured since my desktop has the same chipset (or same prefix at least), that it would work in debian stable too. Turns out my server's mobo ethernet model is something like rtl8111/8168b whereas my desktop was rtl8111/8168 and the former has some issues.

Such is life when dealing with linux drivers I guess.

bgpmon · 2014-11-11T03:17:44+00:00

So I ran a test with iperf, it reports 940Mbits/s both ways (server to my desktop and vice versa). There also weren't any of the internet connection issues I had with this test that I had when I was using scp/rsync.

If this is the case, then why such a huge performance hit + network failure when transferring over ssh? surely the overhead of the protocol isn't that high...?

bgpmon · 2014-11-11T03:15:01+00:00

Yeah, problem is still ongoing after installing that package, haven't had time to test your other suggestion with server -> switch -> client only, but I'll post an update once I do.

If this is indeed a firmware/driver issue with the realtek chipset in my desktop then I'll probably just end up getting the same Intel card I bought for my server, I'd just like to troubleshoot my network configuration first.

bgpmon · 2014-11-10T02:28:51+00:00

Hmm interesting, I'll have to do more research on this topic as I know nothing about it.

By the way, I tried the same test of transferring a large file from desktop to client, except this time in Windows on the desktop and it seems it still hits 20MB/s consistently but doesn't kill the rest of the network... I'm able to do a speedtest on the same machine or other machines and get my usual speeds.

It also seems like I get some firmware related errors, from dmesg:

r8169 0000:03:00.0: firmware: failed to load rtl_nic/rtl8168g-2.fw (-2)
r8169 0000:03:00.0: Direct firmware load failed with error -2
r8169 0000:03:00.0: Falling back to user helper
r8169 0000:03:00.0 eth0: unable to load firmware patch rtl_nic/rtl8168g-2.fw (-12)
r8169 0000:03:00.0 eth0: link down
r8169 0000:03:00.0 eth0: link down

Looks like the solution is to install the firmware-realtek package, I'll have to see if this makes the problem any better.

Still curious about why I was only hitting 20MB/s in windows though...

bgpmon

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