While Installing Magento 2 by using Composer & trying to run composer update command as below image.
or
Solution:: To resolve this issue, there are following below setting need to do in php.ini file.
Go to [PHP configuration file PHP.INI File]] & do following
below changes & restart server
max_execution_time = 5000
max_input_time = 5000
memory_limit = 2G
post_max_size = 900M
upload_max_filesize = 900
Once required PHP Settings has been done, need to run composer update again & it will be run successfully.
For my.ini changes
Path= xampp\mysql\bin\my.ini [Default format below]
key_buffer=16M
max_allowed_packet=1M
sort_buffer_size=512K
net_buffer_length=8K
read_buffer_size=256K
read_rnd_buffer_size=512K
myisam_sort_buffer_size=8M
After changes
key_buffer=80M
max_allowed_packet=10M
sort_buffer_size=4M
net_buffer_length=64K
read_buffer_size=1M
read_rnd_buffer_size=2M
myisam_sort_buffer_size=32M