Did DEC build their early computers out of the same parts?

Considering the PDP-8, PDP-7, PDP-9, PDP-1, even though they are completely different architectures (from a programmer’s or compiler’s point of view at least), they have some remarkable similarities in some details.

For example, the microcoded instructions on both the PDP-8 and PDP-7 have cla, cll, cma, cml, and single or double rotations, which conveniently build up small constants in the accumulator.

The same two computers also have exactly the same skip instructions, and a bit in the instruction to indicate an indirect memory access. The same operations are also available in the PDP-1 instruction set, as are, obviously, things like add, and load.

The same two computers also have an optional EAE, which provides another register MQ and some mathematical operations, though the size of MQ obviously varies between 12 and 18 bits.

So straight away, my mind is supposing that there’s some kind of commonality in the implementation as well.

  • Maybe there’s even a single part, which implements all these operations on a bit or group of bits, and which is installed in all these computers to implement a register and ALU.
  • Maybe there’s some part which takes a bitfield from an instruction, and determines which of these operations need to take place (and is thus part of the instruction decoder) and is installed in at least some of these computers.

Are there large subsystems in common between the implementations of both 12-bit and 18-bit PDPs, which are responsible for the patterns and similarities between these two groups of computers?

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Choosing PC for Programming. Fastests C++ app build

I am choosing hardware to build a PC. The ways I want to use it:

Programming C++, Qt, Compiling, deploying

Streaming how I am coding (not games)

Virtualization. Running many instances of VMs or dockers

I am looking for a processor. I do not need to play games at all, but streaming requires at least a nice integrated video chip.

I want the CPU to support the fastest M2 SSD and 32gb of the fastest RAM. The main concern is the CPU choice according to my tasks. Shall I choose AMD with many cores or stay with Intel, which has better single thread performance?

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Is it possible to build hard shell suit with tighter fit to the body

The only hard shell space suit I know of, NASA”s AX-5, was big, bulbous, and seems to be not very comfortable, although offering zero pre breathing, when entering the suit. What I am thinking, is if the hard shell design can be made into tight fitting suit, that will really feel like a suit, not like a personal spaceship that happens to have limbs.

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How can I persuade developers on my team to embrace “You build it, you run it”?

How can I persuade developers on my team to embrace “You build it, you run it”? By that, I have this quote from Werner Vogels in mind:

Giving developers operational responsibilities has greatly enhanced
the quality of the services, both from a customer and a technology
point of view. The traditional model is that you take your software to
the wall that separates development and operations, and throw it over
and then forget about it. Not at Amazon. You build it, you run it.
This brings developers into contact with the day-to-day operation of
their software. It also brings them into day-to-day contact with the
customer. This customer feedback loop is essential for improving the
quality of the service.

I’m specifically thinking of a set of developers that:

  • Were hired into a developer role, with little/no mention of ops-related tasks.
  • Traditionally have “thrown code over the wall” to an ops team.
  • Traditionally have a 9-5 work schedule, and are actively hostile to the idea of “pager duty”, participating in disaster recovery, writing post-mortems, etc, especially outside of normal business hours. (Note: I only have very infrequent outages in mind for this; I am not proposing that we add after-hours customer support to this team’s workload.)
  • Are not currently responsible for writing/supporting monitoring or alerting on their applications.

Suppose there is a team that is rapidly developing new cloud micro-services with a profile that is getting to be such that handing these services off to an ops team is sub-optimal because they can’t keep up in regards to gaining deep knowledge of the services that is required to effectively manage and monitor them. “You build it, you run it” would work better for this team because tasks could delegated to each responsible team member. So this team would begin taking part in designing infrastructure, monitoring/alerting tools for the services, and (very infrequently) responding to outage events.

I am specifically interested in methodologies, backed up by real world examples. How this been successfully implemented in other workplaces, and if there any canonical steps to follow while implementing this? Any links to write-ups that can support answers would be very helpful.

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Restart agent for each build

How do I configure jenkins to restart the agent for each build?

I tried to use “launch method: launch agent via execution of command on the master” in combintation with “availability: take this agent online when in demand, and offline when idle” but it has two drawbacks:

  1. (not critical) build starts with a delay of about one minute.
  2. (critical) the node goes offline only a minute after the end of the build, and if another build starts at that time, the same still running agent will be used (even if there are several similarly configured free nodes).

There is even a plugin (scripted cloud plugin) that, according to the description, should be suitable, but it does not work, probably because its code is outdated.

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How to use the “build a community around your business” new Facebook feature?

Facebook added a new feature that encourages you to create a Facebook group associated with the Facebook page of your business. Supposedly this would be better for your business. So far, after you associate a page with a group, I’ve seen these features.

  • The Facebook page becomes admin of the group
  • The Facebook page is linked in the top part of the group
  • The Facebook page is linked at the right of the group
  • The group is linked in the Facebook page
  • They encourage you to create a post in your Facebook page for promoting the associated Facebook group.

But I haven’t seen any change in activity neither in the Facebook page nor the Facebook group. Is there anything more you can do with these features? or are there more features related to this I havent seen?

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Which build system should I prefer if I want to distribute tex files?

I want to improve some existing Makefiles in a project where everything is kept as tex files. However, running make pollute the directory with intermediate files and the current Makefile does not make a great job at compiling multiple times if needed.

I want to dispatch the intermediate files in a build directory so that they do not pollute the source directory but are still available if I want to recompile fast.

I have three solutions: standard make (however it would be a bit time consuming if I want to get everything right), latexmk (it seems to be on most machines but is not part of the base distribution of most latex distributions) or rubber (probably not available by default).

I would like to use rubber, but using latexmk or make seems safer. Which of them could I consider to be installed on a “standard” machine? Is it a problem to require rubber or latexmk for building tex files?

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Build Error Unable to merge dex in Unity

I am quite new interms of using Unity and upon downloading the package from Admob ad setting it up I get this error when I build the game.

CommandInvokationFailure: Gradle build failed. 
C:/Program Files/Java/jdk1.8.0_161binjava.exe -classpath "C:Program FilesUnityEditorDataPlaybackEnginesAndroidPlayerToolsgradlelibgradle-launcher-4.2.1.jar" org.gradle.launcher.GradleMain "-Dorg.gradle.jvmargs=-Xmx2048m" "assembleDebug"


FAILURE: Build failed with an exception.

* What went wrong:
Execution failed for task ':transformDexArchiveWithExternalLibsDexMergerForDebug'.
> java.lang.RuntimeException: java.lang.RuntimeException: com.android.builder.dexing.DexArchiveMergerException: Unable to merge dex

* Try:
Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output.

* Get more help at https://help.gradle.org

:preBuild UP-TO-DATE
:preDebugBuild UP-TO-DATE
:compileDebugAidl UP-TO-DATE
:compileDebugRenderscript UP-TO-DATE
:checkDebugManifest UP-TO-DATE
:generateDebugBuildConfig UP-TO-DATE
:prepareLintJar UP-TO-DATE
:generateDebugResValues UP-TO-DATE
:generateDebugResources UP-TO-DATE
:mergeDebugResources UP-TO-DATE
:createDebugCompatibleScreenManifests UP-TO-DATE
:splitsDiscoveryTaskDebug UP-TO-DATE
:javaPreCompileDebug UP-TO-DATE
:compileDebugJavaWithJavac UP-TO-DATE
:compileDebugNdk NO-SOURCE
:compileDebugSources UP-TO-DATE
:mergeDebugShaders UP-TO-DATE
:compileDebugShaders UP-TO-DATE
:generateDebugAssets UP-TO-DATE
:transformClassesWithDexBuilderForDebug UP-TO-DATE
:transformDexArchiveWithExternalLibsDexMergerForDebug FAILED
19 actionable tasks: 4 executed, 15 up-to-date
exit code: 1
UnityEditor.Android.Command.WaitForProgramToRun (UnityEditor.Utils.Program p, UnityEditor.Android.WaitingForProcessToExit waitingForProcessToExit, System.String errorMsg)
UnityEditor.Android.Command.Run (System.Diagnostics.ProcessStartInfo psi, UnityEditor.Android.WaitingForProcessToExit waitingForProcessToExit, System.String errorMsg)
UnityEditor.Android.AndroidJavaTools.RunJava (System.String args, System.String workingdir, System.Action`1 progress, System.String error)
UnityEditor.Android.GradleWrapper.Run (UnityEditor.Android.AndroidJavaTools javaTools, System.String workingdir, System.String task, System.Action`1 progress)
Rethrow as GradleInvokationException: Gradle build failed
UnityEditor.Android.GradleWrapper.Run (UnityEditor.Android.AndroidJavaTools javaTools, System.String workingdir, System.String task, System.Action`1 progress)
UnityEditor.Android.PostProcessor.Tasks.BuildGradleProject.Execute (UnityEditor.Android.PostProcessor.PostProcessorContext context)
UnityEditor.Android.PostProcessor.PostProcessRunner.RunAllTasks (UnityEditor.Android.PostProcessor.PostProcessorContext context)
UnityEngine.GUIUtility:ProcessEvent(Int32, IntPtr)

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V-sync won’t disable in android build

As the title suggests I am having issues with v-sync on android. I’ve set the v sync Count to Don't sync in the qualitySettings panel for the used quality level. However when i run my application on the samsung galaxy S6 its having a constant fps of ~15 due to waiting on vsync to happen (where it is ~60 fps with some spikes to 30 without v-sync).

profiler with v-sync tracked: enter image description here
profiler without v-sync tracked: enter image description here

As you can see it is crealy caused by v-sync happening. What i find strangest about this is that this only started happening a couple of days ago, and was working fine before. Even going back to a commit that 100% worked before v-sync starts messing it up.

I’m using Unity 2017.2.1f1. And have not done any updates to my android version.

Could this be caused by my phone forcing v-sync in some way? and if it is can i turn that off somehwere?

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Failed to build: Error parsing reference: “microsoft/dotnet:2.1-runtime AS base” is not a valid repository/tag:

I got the below error when build docker for console application using .net core.

Step 1/15 : FROM microsoft/dotnet:2.1-runtime AS base
Error parsing reference: “microsoft/dotnet:2.1-runtime AS base” is not a valid repository/tag: invalid reference format

My Dockerfile looks below

FROM microsoft/dotnet:2.1-sdk AS build
COPY ConsoleApp2/ConsoleApp2.csproj ConsoleApp2/
RUN dotnet restore ConsoleApp2/ConsoleApp2.csproj
COPY . .
WORKDIR /src/ConsoleApp2
RUN dotnet build ConsoleApp2.csproj -c Release -o /app

FROM build AS publish
RUN dotnet publish ConsoleApp2.csproj -c Release -o /app

FROM base AS final
COPY --from=publish /app .
ENTRYPOINT ["dotnet", "ConsoleApp2.dll"]

My docker version is

Docker version 17.03.1-ce-rc1, build 3476dbf

Can some one suggest what I am doing wrong in this.
Thanks in advance.

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