cpu

JavaFX 8 QuantumRenderer high CPU usage

南楼画角 提交于 2019-12-03 04:51:44
I have a JavaFX APP containing two listviews displaying incoming customer orders (using a custom cellfactory) received from my server. I also have a few tableview displaying information from a Postgres database (this are spread across a few tabs inside a tabpane). The user has to take an order (by clicking on it), and enter a few information inside textboxes. The application was initially written an deployed using Java7. I had no problem whatsoever. But recently I decided to switch to Java8. I modified my code to use lambdas and added a few extras stuff to the app: a timeline to check and

What is faster (x < 0) or (x == -1)?

|▌冷眼眸甩不掉的悲伤 提交于 2019-12-03 04:48:20
问题 Variable x is int with possible values: -1, 0, 1, 2, 3 . Which expression will be faster (in CPU ticks): 1. (x < 0) 2. (x == -1) Language: C/C++, but I suppose all other languages will have the same. P.S. I personally think that answer is (x < 0) . More widely for gurus: what if x from -1 to 2^30 ? 回答1: That depends entirely on the ISA you're compiling for, and the quality of your compiler's optimizer. Don't optimize prematurely: profile first to find your bottlenecks . That said, in x86, you

CPU throttling in C++

纵饮孤独 提交于 2019-12-03 04:11:49
I was just wondering if there is an elegant way to set the maximum CPU load for a particular thread doing intensive calculations. Right now I have located the most time consuming loop in the thread (it does only compression) and use GetTickCount() and Sleep() with hardcoded values. It makes sure that the loop continues for a certain period of time and than sleeps for a certain minimal time. It more or less does the job i.e. guarantees that the thread will not use more than 50% of CPU. However behavior is dependent on the number of CPU cores (huge disadvantage) and simply ugly (smaller

Redis performance on a multi core CPU

那年仲夏 提交于 2019-12-03 03:59:09
问题 I am looking around redis to provide me an intermediate cache storage with a lot of computation around set operations like intersection and union. I have looked at the redis website, and found that the redis is not designed for a multi-core CPU. My question is, Why is it so ? Also, if yes, how can we make 100% utilization of CPU resources with redis on a multi core CPU's. 回答1: I have looked at the redis website, and found that the redis is not designed for a multi-core CPU. My question is,

High CPU usage with XNA

跟風遠走 提交于 2019-12-03 03:54:32
I just noticed today, that when I compile and run a new XNA 4.0 game, one of CPU threads is running at 100% and the framerate drops to 54 FPS. The weird thing is that sometimes it works at 60 FPS, but then it just drops to 54 FPS. I haven't noticed this behaviour before, so I don't know if this is normal. I uninstalled my antivirus and reinstalled XNA Game Studio, XNA Redistributable and .NET Framework 4. If I set IsFixedTimeStep to false, the game runs at 60 FPS and CPU usage is minimal (1-2%). but as far as I know, this requires me to do velocity calculations using ElapsedGameTime, but I don

Why are GPUs more powerful than CPUs [closed]

生来就可爱ヽ(ⅴ<●) 提交于 2019-12-03 03:49:33
问题 Closed. This question is off-topic. It is not currently accepting answers. Want to improve this question? Update the question so it's on-topic for Stack Overflow. Closed 7 years ago . How are GPUs more faster then CPUs? I've read articles that talk about how GPU's are much faster in breaking passwords than CPUs. If thats the case then why can't CPUs be designed in the same way as GPUs to be even in speed? 回答1: GPUs are designed with one goal in mind: process graphics really fast. Since this

How to use all CPU cores/threads when running Android Studio gradle build?

跟風遠走 提交于 2019-12-03 03:46:58
问题 I'm looking for a parameter or configuration in Android Studio / Gradle, that can set the build so it will use all of my CPU cores during build time. i.e. If I have a quad-core CPU and each core is running 8 threads, how can I optimize the build so it will use every resource it could get (parallel of course)? Thank you! 回答1: in the local.properties file in my project I have org.gradle.daemon=true org.gradle.parallel=true org.gradle.configureondemand=true additionally you can specify org

Android Get Processor Model

微笑、不失礼 提交于 2019-12-03 03:34:16
I want to get Processor Model similar to DU Booster. CPU model contains ARM processor version and revision. For Example: ARMv7 Processor rev 3 (v7l) I have tried this System.getProperty("os.arch") which returns only architecture and String[] args = {"/system/bin/cat", "/proc/cpuinfo"}; to get CPU info. I am able to get the right information in some of the devices but not in all. I tried this in Asus Fonepad 7 which doesn't return the property of the Processor(but returns processor(small p) It returns like processor : 0 vendor_id : GenuineIntel cpu family : 6 model : 53 model name : Intel(R)

descriptor concept in NIC

大兔子大兔子 提交于 2019-12-03 03:13:34
问题 I am trying to understand the concept of Rx and Tx descriptors used in Network driver code. Are Descriptors in software(RAM) or hardware (NIC card). How do they get filled. EDIT: So in a Realtek card driver code. I have a following struct defined. struct Desc { uint32_t opts1; uint32_t opts2; uint64_t addr; }; txd->addr = cpu_to_le64(mapping); txd->opts2 = cpu_to_le32(opts2); txd->opts1 = cpu_to_le32(opts1 & ~DescOwn); So are the opts1 and opts2 and there bits like DescOwn card specific? Will

why does perf stat show “stalled-cycles-backend” as <not supported>?

◇◆丶佛笑我妖孽 提交于 2019-12-03 03:10:14
问题 Running perf stat ls shows this: Performance counter stats for 'ls': 1.388670 task-clock # 0.067 CPUs utilized 2 context-switches # 0.001 M/sec 0 cpu-migrations # 0.000 K/sec 266 page-faults # 0.192 M/sec 3515391 cycles # 2.531 GHz 2096636 stalled-cycles-frontend # 59.64% frontend cycles idle <not supported> stalled-cycles-backend 2927468 instructions # 0.83 insns per cycle # 0.72 stalled cycles per insn 615636 branches # 443.328 M/sec 22172 branch-misses # 3.60% of all branches 0.020657192