此HTOP输出中的列VIRT是什么意思？它呈红色并加粗。
我正在运行一个包含 4个节点的弹性搜索群集，并为大量数据编制索引。
它始终显示绿色健康。
这是一个DigitalOcean Droplet，具有 4GB RAM和2个CPU 。我将heapsize设置为 2gb（-Xms和-Xmx）。
这是RAM内存的开销吗？
1 [||||| 9.4%] Tasks: 26, 122 thr; 2 running
2 [||| 4.3%] Load average: 0.25 0.47 0.65
Mem[||||||||||||||||||||||||||||||2592/3954MB] Uptime: 2 days, 01:05:57
Swp[ 0/0MB]
PID USER PRI NI VIRT RES SHR S CPU% MEM% TIME+ Command
9629 root 20 0 16.2G 2516M 97360 S 12.0 63.6 27h02:30 /usr/bin/java -Xms256m -Xmx1g -Xss256k -
21564 root 20 0 16.2G 2516M 97360 S 4.0 63.6 1:12.17 /usr/bin/java -Xms256m -Xmx1g -Xss256k -
9644 root 20 0 16.2G 2516M 97360 S 1.0 63.6 47:39.34 /usr/bin/java -Xms256m -Xmx1g -Xss256k -
20451 root 20 0 25808 2020 1208 R 0.0 0.0 25:19.48 htop
9654 root 20 0 16.2G 2516M 97360 S 1.0 63.6 5:43.32 /usr/bin/java -Xms256m -Xmx1g -Xss256k -
9651 root 20 0 16.2G 2516M 97360 S 0.0 63.6 6:34.53 /usr/bin/java -Xms256m -Xmx1g -Xss256k -
9653 root 20 0 16.2G 2516M 97360 S 1.0 63.6 1:46.23 /usr/bin/java -Xms256m -Xmx1g -Xss256k -
21565 root 20 0 16.2G 2516M 97360 S 0.0 63.6 1:12.48 /usr/bin/java -Xms256m -Xmx1g -Xss256k -
21563 root 20 0 16.2G 2516M 97360 S 0.0 63.6 1:11.12 /usr/bin/java -Xms256m -Xmx1g -Xss256k -
21472 root 20 0 16.2G 2516M 97360 S 0.0 63.6 1:15.85 /usr/bin/java -Xms256m -Xmx1g -Xss256k -
9652 root 20 0 16.2G 2516M 97360 S 0.0 63.6 5:40.13 /usr/bin/java -Xms256m -Xmx1g -Xss256k -
21562 root 20 0 16.2G 2516M 97360 S 0.0 63.6 1:10.93 /usr/bin/java -Xms256m -Xmx1g -Xss256k -
9631 root 20 0 16.2G 2516M 97360 S 0.0 63.6 1h19:18 /usr/bin/java -Xms256m -Xmx1g -Xss256k -
9632 root 20 0 16.2G 2516M 97360 S 0.0 63.6 1h19:19 /usr/bin/java -Xms256m -Xmx1g -Xss256k -
9633 root 20 0 16.2G 2516M 97360 S 0.0 63.6 7h19:13 /usr/bin/java -Xms256m -Xmx1g -Xss256k -
9850 root 20 0 16.2G 2516M 97360 S 0.0 63.6 18:16.00 /usr/bin/java -Xms256m -Xmx1g -Xss256k -
9634 root 20 0 16.2G 2516M 97360 S 0.0 63.6 1h29:54 /usr/bin/java -Xms256m -Xmx1g -Xss256k -
9722 root 20 0 16.2G 2516M 97360 S 0.0 63.6 50:24.42 /usr/bin/java -Xms256m -Xmx1g -Xss256k -
9703 root 20 0 16.2G 2516M 97360 S 0.0 63.6 4h25:50 /usr/bin/java -Xms256m -Xmx1g -Xss256k -
9704 root 20 0 16.2G 2516M 97360 S 0.0 63.6 4h26:01 /usr/bin/java -Xms256m -Xmx1g -Xss256k -
9662 root 20 0 16.2G 2516M 97360 S 0.0 63.6 1:19.60 /usr/bin/java -Xms256m -Xmx1g -Xss256k -
9669 root 20 0 16.2G 2516M 97360 S 0.0 63.6 0:08.13 /usr/bin/java -Xms256m -Xmx1g -Xss256k -
9665 root 20 0 16.2G 2516M 97360 S 0.0 63.6 6:39.74 /usr/bin/java -Xms256m -Xmx1g -Xss256k -
385 syslog 20 0 243M 1696 872 S 0.0 0.0 0:13.37 rsyslogd -c5
397 syslog 20 0 243M 1696 872 S 0.0 0.0 0:05.58 rsyslogd -c5
9640 root 20 0 16.2G 2516M 97360 S 0.0 63.6 0:24.60 /usr/bin/java -Xms256m -Xmx1g -Xss256k -
9647 root 20 0 16.2G 2516M 97360 S 0.0 63.6 0:10.90 /usr/bin/java -Xms256m -Xmx1g -Xss256k -
9635 root 20 0 16.2G 2516M 97360 S 0.0 63.6 0:38.98 /usr/bin/java -Xms256m -Xmx1g -Xss256k -
950 root 20 0 15988 664 488 S 0.0 0.0 0:21.99 /usr/sbin/irqbalance
9645 root 20 0 16.2G 2516M 97360 S 0.0 63.6 0:19.28 /usr/bin/java -Xms256m -Xmx1g -Xss256k -
9700 root 20 0 16.2G 2516M 97360 S 0.0 63.6 0:10.25 /usr/bin/java -Xms256m -Xmx1g -Xss256k -
19171 root 20 0 86232 2316 1364 S 0.0 0.1 0:10.56 sshd: root@pts/0
9648 root 20 0 16.2G 2516M 97360 S 0.0 63.6 0:09.37 /usr/bin/java -Xms256m -Xmx1g -Xss256k -
9639 root 20 0 16.2G 2516M 97360 S 0.0 63.6 0:32.61 /usr/bin/java -Xms256m -Xmx1g -Xss256k -
9642 root 20 0 16.2G 2516M 97360 S 0.0 63.6 3:04.59 /usr/bin/java -Xms256m -Xmx1g -Xss256k -
9643 root 20 0 16.2G 2516M 97360 S 0.0 63.6 0:37.35 /usr/bin/java -Xms256m -Xmx1g -Xss256k -
9649 root 20 0 16.2G 2516M 97360 S 0.0 63.6 0:55.92 /usr/bin/java -Xms256m -Xmx1g -Xss256k -
9650 root 20 0 16.2G 2516M 97360 S 0.0 63.6 0:15.67 /usr/bin/java -Xms256m -Xmx1g -Xss256k -
9706 root 20 0 16.2G 2516M 97360 S 0.0 63.6 0:51.00 /usr/bin/java -Xms256m -Xmx1g -Xss256k -
9705 root 20 0 16.2G 2516M 97360 S 0.0 63.6 0:38.98 /usr/bin/java -Xms256m -Xmx1g -Xss256k -
9667 root 20 0 16.2G 2516M 97360 S 0.0 63.6 0:08.34 /usr/bin/java -Xms256m -Xmx1g -Xss256k -
9646 root 20 0 16.2G 2516M 97360 S 0.0 63.6 0:10.10 /usr/bin/java -Xms256m -Xmx1g -Xss256k -
9668 root 20 0 16.2G 2516M 97360 S 0.0 63.6 0:07.83 /usr/bin/java -Xms256m -Xmx1g -Xss256k -
9666 root 20 0 16.2G 2516M 97360 S 0.0 63.6 0:08.01 /usr/bin/java -Xms256m -Xmx1g -Xss256k -
398 syslog 20 0 243M 1696 872 S 0.0 0.0 0:01.40 rsyslogd -c5
632 root 20 0 50044 1648 1036 S 0.0 0.0 0:02.10 /usr/sbin/sshd -D
1 root 20 0 24300 1644 740 S 0.0 0.0 0:01.80 /sbin/init
我可以购买更多机器，但我不知道哪个更好：另一台机器VS更多内存。
更新：一个流程的第一行和最后一行pmap
root@es2:~# pmap -d 3589
3589: /usr/bin/java -Xms256m -Xmx1g -Xss256k -Djava.awt.headless=true -XX:+UseParNewGC -XX:+UseConcMarkSweepGC -XX:CMSInitiatingOccupancyFraction=75 -XX:+UseCMSInitiatingOccupancyOnly -XX:+HeapDumpOnOutOfMemoryError -Delasticsearch -Des.foreground=yes -Des.path.home=/root/elasticsearch -cp :/root/elasticsearch/lib/elasticsearch-1.1.1.jar:/root/elasticsearch/lib/*:/root/elasticsearch/lib/sigar/* -Xmx2g -Xms2g -Des.node.name=es2 -Des.node.data=true -Des.node.master=false org.elasticsearch.bootstrap.Elasticsearch
Address Kbytes Mode Offset Device Mapping
0000000000400000 4 r-x-- 0000000000000000 0fd:00000 java
0000000000600000 4 r---- 0000000000000000 0fd:00000 java
0000000000601000 4 rw--- 0000000000001000 0fd:00000 java
000000000188d000 132 rw--- 0000000000000000 000:00000 [ anon ]
0000000775a00000 2118400 rw--- 0000000000000000 000:00000 [ anon ]
00000007f6ec0000 37696 rw--- 0000000000000000 000:00000 [ anon ]
00000007f9390000 111040 rw--- 0000000000000000 000:00000 [ anon ]
00007f6cb0132000 4872 r--s- 0000000000000000 0fd:00000 _8d.fdt
00007f6cb05f4000 5792 r--s- 0000000000000000 0fd:00000 _8d_es090_0.tim
00007f6cb0b9c000 6208 r--s- 0000000000000000 0fd:00000 _8c.fdt
00007f6cb11ac000 6548 r--s- 0000000000000000 0fd:00000 _a0.fdt
00007f6cb1811000 7648 r--s- 0000000000000000 0fd:00000 _a0_es090_0.tim
00007f6cb1f89000 5356 r--s- 0000000000000000 0fd:00000 _78.fdt
00007f6cb24c4000 6236 r--s- 0000000000000000 0fd:00000 _78_es090_0.tim
....
.......
.... (huge text)
....
......
..
00007f703dc6e000 4 rw--- 0000000000007000 0fd:00000 librt-2.15.so
00007f703dc6f000 84 r-x-- 0000000000000000 0fd:00000 libgcc_s.so.1
00007f703dc84000 2044 ----- 0000000000015000 0fd:00000 libgcc_s.so.1
00007f703de83000 4 r---- 0000000000014000 0fd:00000 libgcc_s.so.1
00007f703de84000 4 rw--- 0000000000015000 0fd:00000 libgcc_s.so.1
00007f703de85000 1004 r-x-- 0000000000000000 0fd:00000 libm-2.15.so
00007f703df80000 2044 ----- 00000000000fb000 0fd:00000 libm-2.15.so
00007f703e17f000 4 r---- 00000000000fa000 0fd:00000 libm-2.15.so
00007f703e180000 4 rw--- 00000000000fb000 0fd:00000 libm-2.15.so
00007f703e181000 904 r-x-- 0000000000000000 0fd:00000 libstdc++.so.6.0.16
00007f703e263000 2044 ----- 00000000000e2000 0fd:00000 libstdc++.so.6.0.16
00007f703e462000 32 r---- 00000000000e1000 0fd:00000 libstdc++.so.6.0.16
00007f703e46a000 8 rw--- 00000000000e9000 0fd:00000 libstdc++.so.6.0.16
00007f703e46c000 84 rw--- 0000000000000000 000:00000 [ anon ]
00007f703e481000 10988 r-x-- 0000000000000000 0fd:00000 libjvm.so
00007f703ef3c000 2048 ----- 0000000000abb000 0fd:00000 libjvm.so
00007f703f13c000 608 r---- 0000000000abb000 0fd:00000 libjvm.so
00007f703f1d4000 140 rw--- 0000000000b53000 0fd:00000 libjvm.so
00007f703f1f7000 180 rw--- 0000000000000000 000:00000 [ anon ]
00007f703f224000 88 r-x-- 0000000000000000 0fd:00000 libz.so.1.2.3.4
00007f703f23a000 2044 ----- 0000000000016000 0fd:00000 libz.so.1.2.3.4
00007f703f439000 4 r---- 0000000000015000 0fd:00000 libz.so.1.2.3.4
00007f703f43a000 4 rw--- 0000000000016000 0fd:00000 libz.so.1.2.3.4
00007f703f43b000 96 r-x-- 0000000000000000 0fd:00000 libpthread-2.15.so
00007f703f453000 2044 ----- 0000000000018000 0fd:00000 libpthread-2.15.so
00007f703f652000 4 r---- 0000000000017000 0fd:00000 libpthread-2.15.so
00007f703f653000 4 rw--- 0000000000018000 0fd:00000 libpthread-2.15.so
00007f703f654000 16 rw--- 0000000000000000 000:00000 [ anon ]
00007f703f658000 8 r-x-- 0000000000000000 0fd:00000 libdl-2.15.so
00007f703f65a000 2048 ----- 0000000000002000 0fd:00000 libdl-2.15.so
00007f703f85a000 4 r---- 0000000000002000 0fd:00000 libdl-2.15.so
00007f703f85b000 4 rw--- 0000000000003000 0fd:00000 libdl-2.15.so
00007f703f85c000 1748 r-x-- 0000000000000000 0fd:00000 libc-2.15.so
00007f703fa11000 2048 ----- 00000000001b5000 0fd:00000 libc-2.15.so
00007f703fc11000 16 r---- 00000000001b5000 0fd:00000 libc-2.15.so
00007f703fc15000 8 rw--- 00000000001b9000 0fd:00000 libc-2.15.so
00007f703fc17000 20 rw--- 0000000000000000 000:00000 [ anon ]
00007f703fc1c000 52 r-x-- 0000000000000000 0fd:00000 libjli.so
00007f703fc29000 2044 ----- 000000000000d000 0fd:00000 libjli.so
00007f703fe28000 4 r---- 000000000000c000 0fd:00000 libjli.so
00007f703fe29000 4 rw--- 000000000000d000 0fd:00000 libjli.so
00007f703fe2a000 136 r-x-- 0000000000000000 0fd:00000 ld-2.15.so
00007f703fe4c000 32 r--s- 000000000005a000 0fd:00000 lucene-codecs-4.7.2.jar
00007f703fe54000 16 r--s- 0000000000085000 0fd:00000 localedata.jar
00007f703fe58000 8 r--s- 0000000000012000 0fd:00000 zipfs.jar
00007f703fe5a000 12 r--s- 0000000000032000 0fd:00000 sunjce_provider.jar
00007f703fe5d000 16 r--s- 000000000003b000 0fd:00000 sunpkcs11.jar
00007f703fe61000 556 rw--- 0000000000000000 000:00000 [ anon ]
00007f703feec000 72 rw--- 0000000000000000 000:00000 [ anon ]
00007f703fefe000 220 rw--- 0000000000000000 000:00000 [ anon ]
00007f703ff35000 40 rw--- 0000000000000000 000:00000 [ anon ]
00007f703ff3f000 148 rw--- 0000000000000000 000:00000 [ anon ]
00007f703ff64000 580 rw--- 0000000000000000 000:00000 [ anon ]
00007f703fff5000 32 rw-s- 0000000000000000 0fd:00000 3279
00007f703fffd000 12 ----- 0000000000000000 000:00000 [ anon ]
00007f7040000000 268 rw--- 0000000000000000 000:00000 [ anon ]
00007f7040043000 4 r--s- 0000000000008000 0fd:00000 lucene-memory-4.7.2.jar
00007f7040044000 8 r--s- 000000000000f000 0fd:00000 pulse-java.jar
00007f7040046000 4 r--s- 0000000000007000 0fd:00000 java-atk-wrapper.jar
00007f7040047000 4 r--s- 0000000000002000 0fd:00000 dnsns.jar
00007f7040048000 4 rw--- 0000000000000000 000:00000 [ anon ]
00007f7040049000 4 r---- 0000000000000000 000:00000 [ anon ]
00007f704004a000 8 rw--- 0000000000000000 000:00000 [ anon ]
00007f704004c000 4 r---- 0000000000022000 0fd:00000 ld-2.15.so
00007f704004d000 8 rw--- 0000000000023000 0fd:00000 ld-2.15.so
00007fff9dcbe000 132 rw--- 0000000000000000 000:00000 [ stack ]
00007fff9ddfe000 8 r-x-- 0000000000000000 000:00000 [ anon ]
ffffffffff600000 4 r-x-- 0000000000000000 000:00000 [ anon ]
ffffffffff600000 4 r-x-- 0000000000000000 000:00000 [ anon ]
mapped: 17052740K writeable/private: 2523144K shared: 13562836K
root@es2:~#
答案 0 :(得分：15)
我不再担心VIRT了。
Virtual Memory Usage from Java under Linux, too much memory used
我怀疑首页是为vsyscall目的而分配的（参见What are vdso and vsyscall?）。这意味着虽然您的进程具有映射的16Gb虚拟内存范围，但它在物理内存方面肯定不会使用类似的东西。转到RES条目。
关于是否需要更多机器或更多内存......是否缓慢？你需要对你的瓶颈所在地进行更多的取证，但是那里的htop捕获似乎没有太大的压力。