什么时候使用多线程

?? ?在java编程时，经常会碰到多线程编程，那么到底我们什么时候应该使用多线程呢？

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一高人如是说：

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写道

top - 17:04:19 up 1:56, 4 users, load average: 0.39, 0.40, 0.33Tasks: 93 total, 4 running, 89 sleeping, 0 stopped, 0 zombieCpu(s): 0.4%us, 5.2%sy, 0.0%ni, 82.2%id, 0.0%wa, 2.6%hi, 9.6%si, 0.0%stMem: 1034456k total, 1019500k used, 14956k free, 79572k buffersSwap: 2096472k total, 0k used, 2096472k free, 769248k cached PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND 4609 wusx 20 0 9920 1604 1036 S 3.9 0.2 1:52.06 sshd 5874 wusx 20 0 14220 10m 2348 R 3.6 1.0 2:07.28 ssh 5873 wusx 20 0 6500 1452 1136 R 3.0 0.1 1:30.11 scp 13234 root 20 0 2304 1004 796 R 0.7 0.1 0:00.07 top 2852 root 15 -5 0 0 0 S 0.3 0.0 0:02.83 kjournald 1 root 20 0 2068 616 528 S 0.0 0.1 0:01.89 init 2 root 15 -5 0 0 0 S 0.0 0.0 0:00.01 kthreadd 3 root RT -5 0 0 0 S 0.0 0.0 0:00.00 migration/0 4 root 15 -5 0 0 0 S 0.0 0.0 0:00.00 ksoftirqd/0 5 root RT -5 0 0 0 S 0.0 0.0 0:00.00 watchdog/0 6 root 15 -5 0 0 0 S 0.0 0.0 0:00.03 events/0 7 root 15 -5 0 0 0 S 0.0 0.0 0:00.00 work_on_cpu/0 8 root 15 -5 0 0 0 S 0.0 0.0 0:00.00 khelper 112 root 15 -5 0 0 0 S 0.0 0.0 0:00.67 kblockd/0 114 root 15 -5 0 0 0 S 0.0 0.0 0:00.00 kacpid 115 root 15 -5 0 0 0 S 0.0 0.0 0:00.00 kacpi_notify 229 root 15 -5 0 0 0 S 0.0 0.0 0:00.00 cqueue 231 root 15 -5 0 0 0 S 0.0 0.0 0:00.00 ksuspend_usbd 237 root 15 -5 0 0 0 S 0.0 0.0 0:00.00 khubd 240 root 15 -5 0 0 0 S 0.0 0.0 0:00.01 kseriod 291 root 20 0 0 0 0 S 0.0 0.0 0:00.00 pdflush 292 root 20 0 0 0 0 S 0.0 0.0 0:01.41 pdflush 293 root 15 -5 0 0 0 S 0.0 0.0 0:00.18 kswapd0 294 root 15 -5 0 0 0 S 0.0 0.0 0:00.00 aio/0 546 root 15 -5 0 0 0 S 0.0 0.0 0:00.00 kpsmoused 549 root 15 -5 0 0 0 S 0.0 0.0 0:00.00 hid_compat 607 root 15 -5 0 0 0 S 0.0 0.0 0:00.03 mpt_poll_0 ?

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