canal因为内存原因在Linux无法运行启动（There is insufficient memory for the Java Runtime Environment to continue）

遇到问题：
安装好canal后，在canal/bin目录中启动startup.sh 没有成功，也没有生成canal/logs文件夹中生成canal.log日志,在进程命令中ps -ef | grep canal也查不到canal进程。

在目录canal/logs中查看文件canal_stdout.log，文件内容如下：

# `There is insufficient memory for the Java Runtime Environment to continue.`
# Native memory allocation (mmap) failed to map 1073741824 bytes for committing reserved memory.
# An error report file with more information is saved as:
# /usr/local/canal/bin/hs_err_pid13928.log

第一句话就能看出该错误问题：
内存不足，Java运行时环境无法继续。

There is insufficient memory for the Java Runtime Environment to continue.

更详细的错误日志在文件：/usr/local/canal/bin/hs_err_pid13928.log
复制一段内容：

There is insufficient memory for the Java Runtime Environment to continue.
# Native memory allocation (mmap) failed to map 1073741824 bytes for committing reserved memory.
# Possible reasons:
#   The system is out of physical RAM or swap space
#   The process is running with CompressedOops enabled, and the Java Heap may be blocking the growth of the native heap
# Possible solutions:
#   Reduce memory load on the system
#   Increase physical memory or swap space
#   Check if swap backing store is full
#   Decrease Java heap size (-Xmx/-Xms)
#   Decrease number of Java threads
#   Decrease Java thread stack sizes (-Xss)
#   Set larger code cache with -XX:ReservedCodeCacheSize=
# This output file may be truncated or incomplete.
#
#  Out of Memory Error (os_linux.cpp:2749), pid=13928, tid=0x00007f3dd30d1700
#
# JRE version:  (8.0_261-b12) (build )
# Java VM: Java HotSpot(TM) 64-Bit Server VM (25.261-b12 mixed mode linux-amd64 compressed oops)
# Failed to write core dump. Core dumps have been disabled. To enable core dumping, try "ulimit -c unlimited" before starting Java again

既然是内存原因，那就检查一下自己的内存free -h，发现可用内存仅为133M，应该是内存问题。

• 杀死一些进程
• 增加内存
  （我果断增加了虚拟机的内存，使原来的2G变为4G）

成功运行后可以在canal/logs文件夹中生成canal.log日志。
成功的日志内容为：

2022-05-04 14:16:19.040 [main] INFO  com.alibaba.otter.canal.deployer.CanalLauncher - ## set default uncaught exception handler
2022-05-04 14:16:19.145 [main] INFO  com.alibaba.otter.canal.deployer.CanalLauncher - ## load canal configurations
2022-05-04 14:16:19.198 [main] INFO  com.alibaba.otter.canal.deployer.CanalStarter - ## start the canal server.
2022-05-04 14:16:19.313 [main] INFO  com.alibaba.otter.canal.deployer.CanalController - ## start the canal server[192.168.122.1(192.168.122.1):11111]
2022-05-04 14:16:22.988 [main] INFO  com.alibaba.otter.canal.deployer.CanalStarter - ## the canal server is running now ......

OK！问题解决！