如何增加交换文件的大小？

我是Ubuntu的新手。 我需要将交换文件的大小从8 GB增加到16 GB，我该怎么办？ 是在这个文件/etc/fstab ？

通过命令free -h

  total used free shared buffers cached Mem: 7.6G 4.8G 2.8G 623M 232M 2.5G -/+ buffers/cache: 2.1G 5.5G Swap: 15G 0B 15G 

Answer 1

为了简化操作，这里是我之前编写过的脚本，但针对您的问题进行了修改。 它也可以在我的个人github存储库中找到 。 这使得使用单个命令添加所需的交换量变得容易。

设置步骤：

1. 复制下面的脚本
2. 将它保存为come目录中的某个文件。 将其命名为addswap.sh
3. 打开终端并执行cd
4. 运行chmod +x ./addswap.sh

用法很简单：

 sudo ./addswap.sh INTEGER LETTER 

要添加1千兆字节，你可以使用sudo ./addswap.sh 1 G 要添加1兆字节，请执行sudo ./addswap.sh 1 M

脚本

 #!/bin/bash set -e # bail if anything goes wrong is_root(){ if [ "$( id -u )" -ne 0 ] ; then return 1 fi return 0 } get_swap_amount(){ # Obtain amount of swap in Gigabytes awk '/SwapTotal/{printf "%.2f",($2/1048576)}' /proc/meminfo } make_swap_file(){ # This is the function that does the job of creatig swap file # and enabling it. All files are timestamped printf "Current swap ammount: %f\n" "$(get_swap_amount)" printf "Working on creating swap file\n" DATE=$(date +%s) # append date of creation to filename filename="/swapfile.""$DATE" # File will be /swapfile.$DATE dd if=/dev/zero of="$filename" bs=1"$2" count="$1" chmod 600 "$filename" mkswap "$filename" && swapon "$filename" && printf "\nCreated and turned on %s\n" "$filename" printf "Current swap ammount: %f" "$(get_swap_amount)" } ask_to_enable_on_boot(){ # Prompt user to enable this new swap file on boot. If user # enters y, the swap file will be added to /etc/fstab printf "Do you want to turn on this file at boot?[y/n]\n" read ANSWER case "$ANSWER" in [Yy]) printf "\n%s none swap defaults 0 0\n" "$filename" >> /etc/fstab && printf "\n %s added to /etc/fstab successfuly\n" "$filename" exit 0 ;; [Nn]) printf "Exiting\n" && exit 0 ;; *) printf "Wrong input: %s . Exiting. /etc/fstab not altered\n" "$ANSWER" && exit 1 ;; esac } bad_arguments(){ # check if second argument is a character case "$2" in [AZ]) return 1;; *) return 0;; esac # Check if first argument is a digit. # https://stackoverflow.com/a/3951175/3701431 case "$1" in ''|*[!0-9]*) return 0;; *) return 1 ;; esac } main(){ # Check if we're root and if args are OK. If everything is ok, do stuff if is_root then if [ $# -ne 2 ] || bad_arguments "$@" then printf "%s\n" ">>> ERR: $0: bad or insufficient arguments" > /dev/stderr printf "%s\n" ">>> Usage: $0 INTEGER LETTER" > /dev/stderr exit 2 fi make_swap_file "$@" && ask_to_enable_on_boot else printf ">>> ERR: $0 must run as root\n" > /dev/stderr exit 1 fi } main "$@" 

测试运行

 $ sudo ./addswap.sh 1 G [sudo] password for xieerqi: Current swap ammount: 4.000000 Working on creating swap file 1+0 records in 1+0 records out 1073741824 bytes (1.1 GB, 1.0 GiB) copied, 6.83322 s, 157 MB/s Setting up swapspace version 1, size = 1024 MiB (1073737728 bytes) no label, UUID=8bf1d78d-0a8a-478b-a783-38c5935c362f Created and turned on /swapfile.1498976162 Current swap ammount: 5.000000Do you want to turn on this file at boot?[y/n] Y /swapfile.1498976162 added to /etc/fstab successfuly $