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我刚刚安装了DrRacket,并尝试了“如何设计程序-入门级学生”语言。
Racket - A programmable programming language
Racket - Getting Started
我运行(+ 1 1)
,它花费了十秒钟的时间显示出来:
Welcome to DrRacket, version 6.5 [3m].
Language: Beginning Student; memory limit: 128 MB.
2
>
/usr/share/racket $
find -iname "*htdp*.zo"
./pkgs/htdp-lib/lang/private/compiled/create-htdp-executable_rkt.zo
./pkgs/htdp-lib/lang/compiled/htdp-reader_rkt.zo
./pkgs/htdp-lib/lang/compiled/htdp-beginner-abbr-reader_rkt.zo
./pkgs/htdp-lib/lang/compiled/htdp-langs-save-file-prefix_rkt.zo
./pkgs/htdp-lib/lang/compiled/htdp-advanced-reader_rkt.zo
./pkgs/htdp-lib/lang/compiled/htdp-intermediate-lambda-reader_rkt.zo
./pkgs/htdp-lib/lang/compiled/htdp-advanced_rkt.zo
./pkgs/htdp-lib/lang/compiled/htdp-beginner-abbr_rkt.zo
./pkgs/htdp-lib/lang/compiled/htdp-intermediate_rkt.zo
./pkgs/htdp-lib/lang/compiled/htdp-intermediate-reader_rkt.zo
./pkgs/htdp-lib/lang/compiled/htdp-langs_rkt.zo
./pkgs/htdp-lib/lang/compiled/htdp-beginner_rkt.zo
./pkgs/htdp-lib/lang/compiled/htdp-intermediate-lambda_rkt.zo
./pkgs/htdp-lib/lang/compiled/htdp-beginner-reader_rkt.zo
./pkgs/htdp-doc/scribblings/htdp-langs/compiled/htdp-langs_scrbl.zo
./pkgs/htdp-doc/scribblings/htdp-langs/compiled/htdp-ptr_scrbl.zo
./pkgs/htdp-doc/htdp/compiled/htdp_scrbl.zo
./pkgs/htdp-doc/htdp/compiled/htdp-lib_scrbl.zo
./pkgs/htdp-doc/teachpack/htdp/scribblings/compiled/htdp_scrbl.zo
./pkgs/htdp-doc/teachpack/2htdp/scribblings/compiled/2htdp_scrbl.zo
$ cat /proc/cpuinfo
processor : 0
vendor_id : GenuineIntel
cpu family : 6
model : 28
model name : Intel(R) Atom(TM) CPU N450 @ 1.66GHz
stepping : 10
microcode : 0x107
cpu MHz : 1000.000
cache size : 512 KB
physical id : 0
siblings : 2
core id : 0
cpu cores : 1
apicid : 0
initial apicid : 0
fpu : yes
fpu_exception : yes
cpuid level : 10
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx lm constant_tsc arch_perfmon pebs bts nopl aperfmperf pni dtes64 monitor ds_cpl est tm2 ssse3 cx16 xtpr pdcm movbe lahf_lm dtherm
bugs :
bogomips : 3325.00
clflush size : 64
cache_alignment : 64
address sizes : 32 bits physical, 48 bits virtual
power management:
processor : 1
vendor_id : GenuineIntel
cpu family : 6
model : 28
model name : Intel(R) Atom(TM) CPU N450 @ 1.66GHz
stepping : 10
microcode : 0x107
cpu MHz : 1000.000
cache size : 512 KB
physical id : 0
siblings : 2
core id : 0
cpu cores : 1
apicid : 1
initial apicid : 1
fpu : yes
fpu_exception : yes
cpuid level : 10
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx lm constant_tsc arch_perfmon pebs bts nopl aperfmperf pni dtes64 monitor ds_cpl est tm2 ssse3 cx16 xtpr pdcm movbe lahf_lm dtherm
bugs :
bogomips : 3325.00
clflush size : 64
cache_alignment : 64
address sizes : 32 bits physical, 48 bits virtual
power management:
$ sudo hdparm -I /dev/sda
/dev/sda:
ATA device, with non-removable media
Model Number: Hitachi HTS545016B9A300
Serial Number: 100324PBPB06ECC0K6XL
Firmware Revision: PBBOC60F
Transport: Serial, ATA8-AST, SATA 1.0a, SATA II Extensions, SATA Rev 2.5, SATA Rev 2.6; Revision: ATA8-AST T13 Project D1697 Revision 0b
Standards:
Used: unknown (minor revision code 0x0028)
Supported: 8 7 6 5
Likely used: 8
Configuration:
Logical max current
cylinders 16383 16383
heads 16 16
sectors/track 63 63
--
CHS current addressable sectors: 16514064
LBA user addressable sectors: 268435455
LBA48 user addressable sectors: 312581808
Logical/Physical Sector size: 512 bytes
device size with M = 1024*1024: 152627 MBytes
device size with M = 1000*1000: 160041 MBytes (160 GB)
cache/buffer size = 7208 KBytes (type=DualPortCache)
Form Factor: 2.5 inch
Nominal Media Rotation Rate: 5400
Capabilities:
LBA, IORDY(can be disabled)
Queue depth: 32
Standby timer values: spec'd by Vendor, no device specific minimum
R/W multiple sector transfer: Max = 16 Current = 16
Advanced power management level: 254
Recommended acoustic management value: 128, current value: 254
DMA: mdma0 mdma1 mdma2 udma0 udma1 udma2 udma3 udma4 udma5 *udma6
Cycle time: min=120ns recommended=120ns
PIO: pio0 pio1 pio2 pio3 pio4
Cycle time: no flow control=120ns IORDY flow control=120ns
Commands/features:
Enabled Supported:
* SMART feature set
Security Mode feature set
* Power Management feature set
* Write cache
* Look-ahead
* Host Protected Area feature set
* WRITE_BUFFER command
* READ_BUFFER command
* NOP cmd
* DOWNLOAD_MICROCODE
* Advanced Power Management feature set
Power-Up In Standby feature set
* SET_FEATURES required to spinup after power up
SET_MAX security extension
Automatic Acoustic Management feature set
* 48-bit Address feature set
* Device Configuration Overlay feature set
* Mandatory FLUSH_CACHE
* FLUSH_CACHE_EXT
* SMART error logging
* SMART self-test
* General Purpose Logging feature set
* WRITE_{DMA|MULTIPLE}_FUA_EXT
* 64-bit World wide name
* IDLE_IMMEDIATE with UNLOAD
* WRITE_UNCORRECTABLE_EXT command
* {READ,WRITE}_DMA_EXT_GPL commands
* Segmented DOWNLOAD_MICROCODE
* Gen1 signaling speed (1.5Gb/s)
* Gen2 signaling speed (3.0Gb/s)
* Native Command Queueing (NCQ)
* Host-initiated interface power management
* Phy event counters
* NCQ priority information
Non-Zero buffer offsets in DMA Setup FIS
* DMA Setup Auto-Activate optimization
Device-initiated interface power management
In-order data delivery
* Software settings preservation
* SMART Command Transport (SCT) feature set
* SCT Write Same (AC2)
* SCT Error Recovery Control (AC3)
* SCT Features Control (AC4)
* SCT Data Tables (AC5)
Security:
Master password revision code = 65534
supported
not enabled
not locked
frozen
not expired: security count
supported: enhanced erase
64min for SECURITY ERASE UNIT. 66min for ENHANCED SECURITY ERASE UNIT.
Logical Unit WWN Device Identifier: 5000cca5ffc040a7
NAA : 5
IEEE OUI : 000cca
Unique ID : 5ffc040a7
Checksum: correct
(+ 1 1)
3次-超过5秒钟。
$ time racket -t racket_HTDP_beginner.rkt
2
5.60user 1.04system 0:08.46elapsed 78%CPU (0avgtext+0avgdata 127968maxresident)k
5496inputs+0outputs (46major+40955minor)pagefaults 0swaps
$ time racket -t racket_HTDP_beginner.rkt
2
5.51user 0.67system 0:06.71elapsed 92%CPU (0avgtext+0avgdata 128124maxresident)k
24inputs+0outputs (0major+41790minor)pagefaults 0swaps
$ time racket -t racket_HTDP_beginner.rkt
2
5.41user 0.67system 0:06.55elapsed 92%CPU (0avgtext+0avgdata 128180maxresident)k
0inputs+0outputs (0major+36683minor)pagefaults 0swaps
(+ 1 1)
中运行了
#lang racket
3次-超过2秒。
$ time racket -t racket_lang_racket.rkt
2
2.13user 0.25system 0:02.71elapsed 87%CPU (0avgtext+0avgdata 64996maxresident)k
0inputs+0outputs (0major+12437minor)pagefaults 0swaps
$ time racket -t racket_lang_racket.rkt
2
2.15user 0.25system 0:02.63elapsed 91%CPU (0avgtext+0avgdata 61700maxresident)k
0inputs+0outputs (0major+15853minor)pagefaults 0swaps
$ time racket -t racket_lang_racket.rkt
2
2.28user 0.29system 0:02.89elapsed 89%CPU (0avgtext+0avgdata 61500maxresident)k
0inputs+0outputs (0major+15015minor)pagefaults 0swaps
free -h
时每秒运行
(+ 1 1)
(除了DrRacket和我的基本系统(即窗口管理器等)之外,不运行其他任何应用程序)
#lang racket
尝试一下,看看会发生什么...
最佳答案
我有90%的把握确定您必须等待的原因是Racket的安装未正确完成。
在安装过程中,需要运行setup-plt
程序。它将所有 Racket 文件(.rkt)预编译为所谓的zo文件。如果省略此步骤,则
DrRacket在第一次需要文件时为您进行编译。
在您的情况下(我正在猜测),这是您第一次使用初学者语言,因此需要编译与之相关的所有文件。这需要一段时间。
最好的解决方案是使用http://download.racket-lang.org/中的官方安装程序,它们都包含预编译的zo文件。
如果您碰巧使用过这样的安装程序,请重试-如果问题仍然存在-请提交错误报告(使用DrRacket的“帮助”菜单中的错误报告)。
关于racket - *使用语言 `(+ 1 1)`的速度*极慢(对于 "How To Design Programs - Beginning Student"超过10秒),我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/37508535/
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