1. Betriebssysteme >
  2. Linux Tipps


ArabicEnglishFrenchGermanGreekItalianJapaneseKoreanPersianPolishPortugueseRussianSpanishTurkishVietnamese
Anzeige

Linux Tipps


Suchen

Other suggestions for 17" laptop that's penguin friendly

Linux Tipps vom 16.01.2019 um 01:17 Uhr | Quelle reddit.com

Greetings... To the credit of Linux and System76 I'm about to pass a decade of use from my laptop which is a 17" PanP 5 I bought in 2009. It's now running Kubuntu 18.04 and still runs like a champ. Now my needs have grown to where I need to build Windows and Linux VM's for work and play, and the 4 Gigs of ram and 2 cores just won't cut it. So now I'm pricing laptops. Since System76 has done me well I'm eyeing the Kudu 17" with 16 gigs ram (can expand to 32 gigs later), i7-8750h processor, 120 Gig boot drive, and 2 TB secondary drive .. this is under $1300 which IMO beats most prices I'm seeing elsewhere. What other 17" laptops are out there that I should be considered? I've looked at the Dell XPS as many suggest, but it's like 13" and I really need 17". Also most of the other 17" laptops are around $2K or more, but I need to hang around $1500 or less. Thanks for any input.

submitted by /u/samalex01
[link] [comments]
Newsbewertung

Weiterlesen

Other suggestions for 17" laptop that's penguin friendly

Linux Tipps vom 16.01.2019 um 01:17 Uhr | Quelle reddit.com

Greetings... To the credit of Linux and System76 I'm about to pass a decade of use from my laptop which is a 17" PanP 5 I bought in 2009. It's now running Kubuntu 18.04 and still runs like a champ. Now my needs have grown to where I need to build Windows and Linux VM's for work and play, and the 4 Gigs of ram and 2 cores just won't cut it. So now I'm pricing laptops. Since System76 has done me well I'm eyeing the Kudu 17" with 16 gigs ram (can expand to 32 gigs later), i7-8750h processor, 120 Gig boot drive, and 2 TB secondary drive .. this is under $1300 which IMO beats most prices I'm seeing elsewhere. What other 17" laptops are out there that I should be considered? I've looked at the Dell XPS as many suggest, but it's like 13" and I really need 17". Also most of the other 17" laptops are around $2K or more, but I need to hang around $1500 or less. Thanks for any input.

submitted by /u/samalex01
[link] [comments]
Newsbewertung

Weiterlesen

Trying to make the game I'm developing work on Linux - looking for a playtester

Linux Tipps vom 16.01.2019 um 00:54 Uhr | Quelle reddit.com

Hello,

I'm developing a little game with RPG Maker MV. With this engine, distributing a game build for Linux is supposed to work by just choosing a different checkbox. Unfortunately, I named many files very poorly and was told that these file names would work for Windows, but not for Linux.

I spent the last 2 days renaming every single picture file and re-emplementing them in the game to make the game run on Linux aswell. Now I'd like to make sure that my effort wasn't for nothing.

The game is a 200 MB file and takes about 2 hours to complete (it's only chapter 1). It's a 2D puzzle adventure game in which you play a young dragon who is trying to save the life of his mother. I would be really grateful if someone could playtest it for me. The game will soon be available for free on itch.io and I want to make sure that people have a working game when they download the Linux distribution. Screenshots of the game can be found in my post history. It would be a big relief to know that the game works properly from start to finish on Linux.

submitted by /u/Cygopat
[link] [comments]
Newsbewertung

Weiterlesen

[$] Ringing in a new asynchronous I/O API

Linux Tipps vom 16.01.2019 um 00:09 Uhr | Quelle lwn.net
While the kernel has had support for asynchronous I/O (AIO) since the 2.5 development cycle, it has also had people complaining about AIO for about that long. The current interface is seen as difficult to use and inefficient; additionally, some types of I/O are better supported than others. That situation may be about to change with the introduction of a proposed new interface from Jens Axboe called "io_uring". As might be expected from the name, io_uring introduces just what the kernel needed more than anything else: yet another ring buffer.
Newsbewertung

Weiterlesen

Google Summer of Code mentor projects sought

Linux Tipps vom 16.01.2019 um 00:07 Uhr | Quelle lwn.net
It is that time of year again: Google is looking for mentor projects for the 2019 Summer of Code. "GSoC is a global program that draws university student developers from around the world to contribute to open source. Each student spends three months working on a coding project, with the support of volunteer mentors, for participating open source organizations from late May to August. Last year 1,264 students worked with 206 open source organizations." The application deadline is February 6.
Newsbewertung

Weiterlesen

Chrome OS will soon let you search for and install Linux apps from the launcher

Linux Tipps vom 15.01.2019 um 22:41 Uhr | Quelle reddit.com
submitted by /u/mfilion
[link] [comments]
Newsbewertung

Weiterlesen

NetAuth: lightweight LDAP+Kerberos replacement (for authentication), works over WAN as well.

Linux Tipps vom 15.01.2019 um 21:28 Uhr | Quelle reddit.com
submitted by /u/kvtb
[link] [comments]
Newsbewertung

Weiterlesen

Legality of Releasing the Code for my Steam Emulator (Linux and Windows) under LGPLv3+

Linux Tipps vom 15.01.2019 um 20:17 Uhr | Quelle reddit.com

I want to know if there's a way I can release the code of my steam emulator in a legal way to make it a legit open source project. I see projects like wine and console emulators (the ones that do HLE) that implement proprietary apis which is pretty much the same thing I am doing so there must be a way.

Some information about my steam emulator:

  1. All the code is written by me except the steam SDK headers that I got from somewhere (they are likely a straight copy paste of the official ones). The only libraries used are protobuf and detours (detours is only used on windows in my "experimental" build to hook socket functions to try to prevent games from communicating with online).

  2. I never reversed engineered the steam client directly. The closest I did was ask people I know to run tests I wrote that use the steam api to figure out how it behaves.

  3. My emulator does not attempt to crack any steam DRM like steamstub or CEG or non steam ones. I don't think the steam api itself is DRM but this is just my opinion.

  4. It's written in C++

  5. All the emulator does is implement the steam api in a way that lets you play steam games that use it without using steam. It implements the steam matchmaking and the server stuff so you can play LAN with games that use the steam api for online. It completely removes the steam dependency from steam games.

I started this project because I want to be able to play my game collection in 20 years even if steam is long gone. I want to release it as free software because I want it to grow more but I want to do it properly. I welcome any suggestions or criticism.

Thank you.

submitted by /u/Mr__Goldberg
[link] [comments]
Newsbewertung

Weiterlesen

Linux kernel won't load when KVM is in in auto-detect mode for the keyboard.

Linux Tipps vom 15.01.2019 um 19:33 Uhr | Quelle reddit.com

This post is meant to be informational to some extent, and is not asking for help. Maybe it will save someone else many hours of hair pulling.

So, I just spent way too many hours trying to diagnose a problem. I have an old Zoltac IONITX-L-E motherboard that I wanted to use for my development server. I have an existing system with a Zoltac NM10-B-E, that I wanted to use for something else since it has more SATA ports, so I swapped the boards. Only... when I swapped the boards, the dev system would no longer boot. It would get to the grub menu, and when trying to load the kernel, nothing. No text at all, just nothing. So, I tried to boot Knoppix so I could fix grub..., and nothing. The thing is... I had just put FreeNAS on a computer with this mother board in it, and it booted fine. So, I put the board back in the other case, and it booted right up to FreeNAS. Put it back in the case with the CentOS hard drives, and nothing. I needed my dev server back up, so I put the original mother board back in it, and it came up just fine.

I was curious though... it boots FreeNAS, why not other things. So, I put in the Knoppix thumb drive while it was back in the other case, and it booted fine. Put in a CentOS installer thumb drive, and it booted fine, installed centos fine, and booted up CentOS fine from the hard drive. WTF! I ran diagnostics on the hard drives in the dev system, to make sure it wasn't an error that the SATA controllers were handling differently or something. But both are fine. At that point, I was assuming the risers on the case weren't high enough, so I got a different case, and still wouldn't boot. I ended up holding the board up out of the case to make sure... nothing. I pulled the PSU from the case that it did work in, hooked that up, and... nothing. I put it all back into the other case, and it magically started working again.

At this point, it was getting late into the night, and my tired brain was honestly thinking that something with the grounding on this case was allowing the board to work past some fault or something. I ended up going to sleep. In the morning, I ended up with a more clear mind, and realized the case and PSU was NOT the only difference. When I was trying to use the mother board as my dev system, I had it hooked to my KVM. When I had it in the other case where it worked, I had it hooked up with it's own keyboard and mouse. So, I put the board back in the dev server case, unplugged the KVM, and it booted up just fine. So then I shut it down, hooked up only the display cable, and it still booted just fine (I assumed that would work). Then I plugged in the USB cable that handles keyboard and mouse, and it wouldn't boot... just a blinking cursor. But, I could unplug it, let it boot, and then plug it in, and the KVM worked as intended.

So, the KVM caused Linux (or at least, CentOS and Knoppix), not to boot. Why? I figured it either had to be the mouse or keyboard emulation. So, I disabled mouse emulation, and, still wouldn't boot. The keyboard emulation only has three settings, Mac, Sun, or Auto-detect. By default, it's set to Auto-detect. I changed it to Sun, and the board started booting fine. Something about the Auto-detect feature on the KVM, causes the Linux kernel (again, at least on CentOS and Knoppix) to just not boot (load might be a better term...) on this motherboard. CentOS boots fine when hooked up in auto-detect mode, when using the other original motherboard I had in the system.

For anyone curious, it's a Zoltac IONITX-L-E motherboard, the USB Controller is an NVIDIA MCP79, and the KVM is an IOGEAR GCS1104.

submitted by /u/psyon
[link] [comments]
Newsbewertung

Weiterlesen

Frequent HDD errors

Linux Tipps vom 15.01.2019 um 19:27 Uhr | Quelle reddit.com

Hello, my kubuntu fails to update pretty often saying 'can't write...some config file'. The system boots into BusyBox after restart where I have to do 'fsck' on my / and fix multiple errors.

Does that mean my HDD is going to die soon? I had Windows 10 on that drive before and haven't noticed any errors. What is the best way to check my hard drive?

What is the best way to backup my system on a file level? (not sector by sector backup by 'dd') I did spend some time compiling few packages and configuring my system so I would not want to start over.

Any advises will be greatly appreciated.

submitted by /u/wildcowboypublic
[link] [comments]
Newsbewertung

Weiterlesen

What's the worst thing that happened in the history of Linux?

Linux Tipps vom 15.01.2019 um 19:11 Uhr | Quelle reddit.com
submitted by /u/1337_n00b
[link] [comments]
Newsbewertung

Weiterlesen

[$] Fedora, UUIDs, and user tracking

Linux Tipps vom 15.01.2019 um 18:23 Uhr | Quelle lwn.net

"User tracking" is generally contentious in free-software communities—even if the "tracking" is not really intended to do so. It is often distributions that have the most interest in counting their users, but Linux users tend to be more privacy conscious than users of more mainstream desktop operating systems. The Fedora project recently discussed how to count its users and ways to preserve their privacy while doing so.


Newsbewertung

Weiterlesen

The FSF is 5,000 members strong

Linux Tipps vom 15.01.2019 um 18:05 Uhr | Quelle reddit.com
submitted by /u/fsher
[link] [comments]
Newsbewertung

Weiterlesen

I'm going to work full-time on free software

Linux Tipps vom 15.01.2019 um 17:53 Uhr | Quelle reddit.com
submitted by /u/emersion_fr
[link] [comments]
Newsbewertung

Weiterlesen

Tesla uses Linux for their website

Linux Tipps vom 15.01.2019 um 17:42 Uhr | Quelle reddit.com
submitted by /u/Hans_Bouwman
[link] [comments]
Newsbewertung

Weiterlesen

Entroware Unleash Hades, A Powerful Linux Workstation

Linux Tipps vom 15.01.2019 um 17:14 Uhr | Quelle feedproxy.google.com

AMD RYZEN CPUBritish Linux computer company Entroware has unveiled its latest Linux-powered offering — and it’s something of a beast! The Entroware Hades is the company’s first workstation PC to offer AMD processors and multi-GPU configurations. The base model comes equipped with an octa-core AMD Ryzen 1900X, Nvidia GeForce GT 1030 (2GB) and 16GB RAM and a 120GB SSD. […]

This post, Entroware Unleash Hades, A Powerful Linux Workstation, was written by Joey Sneddon and first appeared on OMG! Ubuntu!.


Newsbewertung

Weiterlesen

How to import photos on Linux with Shotwell

Linux Tipps vom 15.01.2019 um 16:48 Uhr | Quelle addictivetips.com

Do you have a DSLR or digital camera and take lots of pictures? Are you tired of manually importing all of the photos on your camera onto the Linux desktop? If so, you’ll be interested to know about Shotwell: a photo management app for the Linux platform that lets you import photos on Linux from […]

Read How to import photos on Linux with Shotwell by Derrik Diener on AddictiveTips - Tech tips to make you smarter


Newsbewertung

Weiterlesen

An ancient OpenSSH vulnerability

Linux Tipps vom 15.01.2019 um 16:35 Uhr | Quelle lwn.net
An advisory from Harry Sintonen describes several vulnerabilities in the scp clients shipped with OpenSSH, PuTTY, and others. "Many scp clients fail to verify if the objects returned by the scp server match those it asked for. This issue dates back to 1983 and rcp, on which scp is based. A separate flaw in the client allows the target directory attributes to be changed arbitrarily. Finally, two vulnerabilities in clients may allow server to spoof the client output." The outcome is that a hostile (or compromised) server can overwrite arbitrary files on the client side. There do not yet appear to be patches available to address these problems.
Newsbewertung

Weiterlesen

GNOME’s New GTK Theme is Ready for Testing

Linux Tipps vom 15.01.2019 um 16:25 Uhr | Quelle feedproxy.google.com

new gnome gtk adwaita before and afterCast your minds back to December and, amid baubles and wrapping paper, you may recall us sharing some screenshots of a refreshed version of the Adwaita GTK theme, used by GNOME. Now, GNOME”s Matthias Clasen has shared more details on a ‘limited set of theme changes’ being made to Adwaita, and their potential inclusion in […]

This post, GNOME’s New GTK Theme is Ready for Testing, was written by Joey Sneddon and first appeared on OMG! Ubuntu!.


Newsbewertung

Weiterlesen

GNOME’s New GTK Theme is Ready for Testing

Linux Tipps vom 15.01.2019 um 16:25 Uhr | Quelle feedproxy.google.com

new gnome gtk adwaita before and afterCast your minds back to December and, amid baubles and wrapping paper, you may recall us sharing some screenshots of a refreshed version of the Adwaita GTK theme, used by GNOME. Now, GNOME”s Matthias Clasen has shared more details on a ‘limited set of theme changes’ being made to Adwaita, and their potential inclusion in […]

This post, GNOME’s New GTK Theme is Ready for Testing, was written by Joey Sneddon and first appeared on OMG! Ubuntu!.


Newsbewertung

Weiterlesen

linux-steam-integration v0.7.3 released

Linux Tipps vom 15.01.2019 um 16:11 Uhr | Quelle reddit.com
submitted by /u/Vulphere
[link] [comments]
Newsbewertung

Weiterlesen

How to install PHP on Linux

Linux Tipps vom 15.01.2019 um 16:00 Uhr | Quelle addictivetips.com

PHP is one of the core components of the web. If you plan to host a Linux server that delivers web applications, understanding how to install it is a must. Installing the core PHP run-time files on Linux differs, depending on what you’re using, and it can get confusing. For this reason, we’ve decided to show […]

Read How to install PHP on Linux by Derrik Diener on AddictiveTips - Tech tips to make you smarter


Newsbewertung

Weiterlesen

Searching for the cause of dropped packets on Linux

Linux Tipps vom 15.01.2019 um 15:57 Uhr | Quelle reddit.com

Hi all, just wanted to share a recent experience I had investigating a packet drop issue on a linux system. Hope it's useful to anyone facing similar issues.

Recently I was alerted by our monitoring system that it detected network packet loss. The loss was not excessive, only a couple of hundred packets, nothing compared to the billions of packets flowing through our systems. There was no observable degradation of the functionality of the system. The number of lost packets was low and they were TCP packets, so TCP retransmission would overcome the loss. However, packet loss is often an early sign that something is wrong with the systems, i.e. load is building up beyond capacity. So I took the alert seriously and started searching for the cause. There can be various reasons for packet loss. It can be that the network transport is unreliable and packet loss is natural, the network link could be congested, applications cannot handle the offered load. In this case the network link was reliable fibre, the network link was far from congested. The monitoring system indicated that the packet loss was on a linux box running several server applications that process data sent by our trading machines for analysis by our traders. The packet drops were on incoming traffic. The drop count is shown by the ifconfig command.

ens3f0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500 ether 00:0f:53:2b:87:e0 txqueuelen 1000 (Ethernet) RX packets 2155496544 bytes 767987963091 (715.2 GiB) RX errors 0 dropped 69740 overruns 0 frame 0 TX packets 2335238951 bytes 663467243034 (617.9 GiB) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0 device interrupt 16 

It seemed most likely that the applications received more traffic than they could handle. Given that on this box one application was running close to its maximum capacity, I expected that this application could not handle the load during some periods during the day, something we had seen before. So I analyzed the performance metrics of this application. CPU load was not very high, the incoming traffic was not out of the ordinary. All metrics indicated that the application was running normally. Nothing indicated that it was overloaded.

https://i.redd.it/j27iclftkla21.png

This is a single threaded application handling approximately 7000 TCP connections. The CPU load showed some spikes, but nothing excessive. Some of the packet loss periods coincided with those spikes, but not all. Also some periods of high load did not show any packet loss. The same held for the network traffic measured at the NIC level. The periods with dropped packets did not coincide with the periods having the highest packet rate. I also checked the other applications on the box and as expected their load was way less and did not show any signs of overload.

This looked odd. The network seems fine, the applications do not seem overload, yet packets are dropped. Could the monitoring system be wrong? We captured network traffic with tcpdump. If the monitoring system showed packet loss, but the TCP streams in the capture do not, then the monitoring system could be wrong. It could still be that the monitoring system is right as the packets are dropped on the machine, possibly after capturing. The capture did show gaps in the TCP sequence numbers. Tcpdump may not be able to capture all traffic and create those gaps by itself. In this case, the gaps were real as later in time the retransmissions for those missing packets could be seen, i.e. the clients sending those packets did not receive acknowledgements and retransmit the packets.

The capture confirmed the alerts from the monitoring system. We learned something useful from the capture though. The packet drops were seen on TCP streams from all applications running on the box, not only for the one heavy application! That means application performance could not be the cause. Still I was not 100% convinced that it was not something in the application. What else could it be? I decided to do an experiment:

  1. Run a server that accepts incoming connections, but does not read any data from the connected socket
  2. Connect a client to the server
  3. Keep sending data from that client to the server

At some point the server should drop the incoming data. How would this packet drop show in the metrics?

During the experiment I watched the output of the netstat -atn command on the machine running the server:

Proto Recv-Q Send-Q Local Address Foreign Address State tcp 5250096 0 172.30.12.53:24232 172.30.12.52:50049 ESTABLISHED 

As expected the size of the receive queue (Recv-Q) kept growing. It grew till ~5MB and then the queue was full, no more packets could be received. Tcpdump showed retransmissions, coming in slower and slower. The TCP exponential backoff algorithm did its work at the client side.

(here comes the last acknowledge packet) 14:59:30.461175 IP 172.30.12.52.50110 > 172.30.12.53.24232: Flags [P.], seq 5021029:5021461, ack 0, win 15, options [nop,nop,TS val 3705262642 ecr 216579590], length 432 14:59:30.501125 IP 172.30.12.53.24232 > 172.30.12.52.50110: Flags [.], ack 5021461, win 32, options [nop,nop,TS val 216579630 ecr 3705262642], length 0 (retransmissions coming in, slower and slower) 14:59:30.501182 IP 172.30.12.52.50110 > 172.30.12.53.24232: Flags [P.], seq 5021461:5021785, ack 0, win 15, options [nop,nop,TS val 3705262682 ecr 216579630], length 324 14:59:30.740948 IP 172.30.12.52.50110 > 172.30.12.53.24232: Flags [P.], seq 5021461:5021785, ack 0, win 15, options [nop,nop,TS val 3705262922 ecr 216579630], length 324 14:59:31.221942 IP 172.30.12.52.50110 > 172.30.12.53.24232: Flags [P.], seq 5021461:5021785, ack 0, win 15, options [nop,nop,TS val 3705263403 ecr 216579630], length 324 

To my surprise the 'dropped' count in ifconfig did not increase! I searched for other metrics to see where those dropped packets showed up. I found that the following counters, displayed by netstat -s incremented with each incoming retransmission.

18415 packets pruned from receive queue because of socket buffer overrun 50 packets pruned from receive queue 

Now I was convinced that the packet drops that we had in our production system were not due to performance issues in the application itself. But then what was it? The packets arrived at the machine, the application can handle the load, still the packets were dropped. What dropped it? As a software developer I was aware of network issues and application performance, but I never really thought about what is between the NIC and my application. Something there must be dropping packets. In between is the network driver and the kernel, something I never really looked into. Now I had to. The NIC, a Solarflare card, has a ring buffer of 1024 slots by default. Every incoming packet is put into this buffer through DMA. Each is 2K and can hold 1 packet at most, i.e. a small packet of only several bytes will occupy a full slot. This ring buffer can be increased to 4096 slots. We did and then there were no more packet drops!

Apparently the buffer overflowed and increasing the buffer stopped the packets from being dropped. Still I felt unsatisfied as I did not really understand why the buffer overflowed. After all the NIC was a 10GB/s interface and the incoming traffic was well below that rate. When a packet arrives at the NIC the following happens:

  1. An IRQ is raised
  2. This IRQ eventually triggers a task net_rx_action
  3. The net_rx_action task takes packets from the NIC ring buffer and puts them in socket buffer (skb) structures
  4. The skb's are passed up to the protocol layers, IP, TCP

The net_rx_action has a limited budget to run. The budget is determined by 2 constraints:

  1. A packet budget defined by net.core.netdev_budget - This is the amount of packets that can be handled at most in a single run.
  2. A time constraint of 2 jiffies.

If either of these constraints is reached, then the task is stopped. Remaining packets will be left in the ring buffer till the task runs again. This is to prevent net_rx_action hogging the kernel. When this happens the squeeze_time counter in the /proc/net/softnet_stat statistics gets incremented. These statistics show 1 line per CPU core. Each counter is 4 bytes. The 3rd counter is the squeeze_time counter. Looking at the core handling the IRQ's from the NIC we saw that the squeeze_time counter got incremented once in a while:

6cbc9e8e 00000000 0005e467 00000000 00000000 00000000 00000000 00000000 00000000 00000000

Monitoring this count showed a pattern similar to the packet drops that we had first. The packet drops stopped due to increased buffer size, but at the times we had drops before we now observed time squeezes. By default the packet budget net.core.netdev_budget is 300. This seems quite a low number and apparently we receive bursts of packets exceeding this number, probably exceeding the default ring buffer size of 1024. Searching the internet showed that the default budget is too low for handling 10GB/s. Hogging the CPU core did not seem to be an issue as we had dedicated one CPU core to handle the network IRQ's. So far this core never exceeded a load of 15%.

Increasing the budget indeed reduced the number of time squeezes. Still I was puzzled why this happened in the first place as the box did not receive anything close to 10GB/s or did it? All traffic rate metrics have a sampling rate of 1s. What if there are some exceptionally large bursts in sub-second intervals?

With the packet drops gone, we captured network traffic once more. This time I made an I/O graph for incoming packets with a 1ms interval using Wireshark to get an insight into traffic rates. This is what I got:

https://i.redd.it/u4bslz60nla21.png

Three sharp peaks stand out and in between lower peaks can be seen.The 3 peaks show that packet rate goes up to ~700 packets/ms. This is quite high and perhaps the rate is even higher on some sub-millisecond intervals. The peaks are caused by hundreds of clients sending a small packet to the server at the same time.

Although the average amount of traffic was moderate, there were micro bursts of traffic due to synchronized behavior of the clients. The micro bursts were the cause of the packet drops we saw. They are somewhat like microscopic denial of service attacks.

Conclusion

When this issue started I thought it would be a case of application performance issues. I did not expect to end up in the depths of the kernel. As with all complex issues, there are multiple causes for the packets loss:

  • Multiple clients sending data in a synchronized manner cause micro traffic bursts at the server
  • The default settings of the net_rx_task kernel task are not sufficient to process these bursts in one go
  • The default size of the ring buffer is too small to buffer all packets from these bursts
  • The packets making up the bursts are small, so the data rate measured in bytes stays well below the maximum

The art of software development requires one to think in layers of abstraction. Running an application requires layers upon layers upon layers with the hardware at the bottom. Most of the time we never really think about all those layers as they just do their job, making themselves invisible to us. When problems arise we search in the top layer, our application. This is where we find most of our problems. But once in a while the problems are in those layers below. To find those you need to be aware what is beneath your application. You need expertise from others. I got help from colleagues with expertise in networks and the Linux kernel to help me out.

In this case there is also the effect from multiple clients behaving in a synchronized way causing those bursts. Every single client worked as expected, but together they did not.

Without our monitoring systems we would not have known about this problem. Most likely the amount of traffic would have grown over time, possibly making the bursts larger or more frequent up to the point where functionality of the system starts to degrade, i.e. unresponsive applications on the trader's desktop. Doing this investigation under such conditions would have been much more stressful.

No matter how well you design and build your systems, unforeseen issues will happen. You need monitoring to find these issues before they become harmful.

Michel de Boer
Engineer at Optiver

submitted by /u/Engineer-at-Optiver
[link] [comments]
Newsbewertung

Weiterlesen

Installing Linux to a portable HDD/SSD

Linux Tipps vom 15.01.2019 um 15:52 Uhr | Quelle reddit.com

Hey, everyone. I just had a quick question regarding installing Linux. I was wondering first of all if it is possible to install Linux to a portable HDD/SSD, and if so, how would I go about doing it. Secondly, could I use a VM to run the install. I know that when you boot up Kali Linux in a VM it first gives yout the boot menu. One of the options is to install it via that menu. Could I possibly use that Boot Menu to install Linux to a portable drive?

submitted by /u/Citizen_Sixteen
[link] [comments]
Newsbewertung

Weiterlesen

Does anyone have a link that explains the origins of *nux's handling of mount points and file systems?

Linux Tipps vom 15.01.2019 um 15:37 Uhr | Quelle reddit.com

I came from the windows world. I can do what I need with linux mounts, but I don't intuitively understand mounting a fs within folders and all that. I'm wondering if a historical overview of why it's done this way will help me. Google just brings up "how-to"s. Thank you in advance.

submitted by /u/ronin1066
[link] [comments]
Newsbewertung

Weiterlesen

When Virus tries to attack Linux

Linux Tipps vom 15.01.2019 um 15:12 Uhr | Quelle reddit.com
submitted by /u/beer118
[link] [comments]
Newsbewertung

Weiterlesen

Status Update on MNT Reform (2019-01-15)

Linux Tipps vom 15.01.2019 um 15:06 Uhr | Quelle reddit.com
submitted by /u/up-sky-7
[link] [comments]
Newsbewertung

Weiterlesen

Tablet as a monitor for linux

Linux Tipps vom 15.01.2019 um 14:49 Uhr | Quelle reddit.com

Ok so a few weeks ago I seen a guy with a setup for his airplane game (flight sim) he had a tablet set up as a monitor on the side that displayed his gauges. Idk if it was set up as a touch screen, either way it was cool.

Is it possible to do that on linux? I have two monitors now and I use them both and still have to use different workspaces. It would be awesome to have a small monitor to display values, sensor info, or just watch a video etc on my Linux (mint 19).

Is there a way to do this? I just fired up my Linux pc for the first time in two years, so I am super rusty now. Can someone point me in a good direction? I googled all over and I am getting very polar opposite information. I just either am googling it wrong, or something.

Thank you for reading and have a good day.

submitted by /u/Silverpathic
[link] [comments]
Newsbewertung

Weiterlesen

Why data scientists love Kubernetes | Opensource.com

Linux Tipps vom 15.01.2019 um 13:51 Uhr | Quelle reddit.com
submitted by /u/NuEd_Fernandes
[link] [comments]
Newsbewertung

Weiterlesen

Boot screen for the back of seat media system on a united airlines flight in the US.

Linux Tipps vom 15.01.2019 um 13:43 Uhr | Quelle reddit.com
submitted by /u/Jsquaredz
[link] [comments]
Newsbewertung

Weiterlesen

Nuclear: A free alternative to Spotify. No DRM. 100% free software. Pulls music from Youtube, Soundcloud and Bandcamp. (Alpha release)

Linux Tipps vom 15.01.2019 um 13:39 Uhr | Quelle reddit.com
submitted by /u/f7ddfd505a
[link] [comments]
Newsbewertung

Weiterlesen

A Good Audio Capture Software

Linux Tipps vom 15.01.2019 um 13:29 Uhr | Quelle reddit.com

Hi me and my friend would like to capture audio of our call conversation. Is there a way to record it and get an mp3 file from a software? Do you know of any?

submitted by /u/mystic-redditor
[link] [comments]
Newsbewertung

Weiterlesen

Getting an IBM AS/400 Midrange computer on the internet

Linux Tipps vom 15.01.2019 um 13:11 Uhr | Quelle reddit.com
submitted by /u/paulcarroty007
[link] [comments]
Newsbewertung

Weiterlesen

Found what resembles an old linux DE in an anime opening sequence!

Linux Tipps vom 15.01.2019 um 11:03 Uhr | Quelle reddit.com
submitted by /u/SilicateWielder
[link] [comments]
Newsbewertung

Weiterlesen

SLES 11 SP3 - Ssh hanging prior to prompting for a password

Linux Tipps vom 15.01.2019 um 10:31 Uhr | Quelle reddit.com

I have an issue where when I ssh onto any user on my SLES11 SP3 server, it takes around 10-15 seconds to return back and prompt me for a password.

An ssh -vvv <user>@<IP> shows the hang is right after this:

debug1: Local version string SSH-2.0-OpenSSH_6.6.1

Can anyone suggest what could be causing this, please?

I have tried adding:

UseDNS No in my sshd_config and bouncing the service, but this produces little difference.

submitted by /u/InquisitiveProgramme
[link] [comments]
Newsbewertung

Weiterlesen

Seitennavigation

Seite 5 von 282 Seiten (Bei Beitrag 140 - 175)
9.850x Beiträge in dieser Kategorie

Auf Seite 4 zurück | Nächste 6 Seite | Letzte Seite
[ 1 ] [ 2 ] [ 3 ] [ 4 ] [5] [ 6 ] [ 7 ] [ 8 ] [ 9 ] [ 10 ] [ 11 ] [ 12 ] [ 13 ] [ 14 ] [ 15 ]