1. vmstat view server memory, CPU and other information
Typically is accomplished by two numeric parameters, the first parameter is the sampling interval, in seconds, the second parameter is the number of samples
r: represents the run queue, if the queue is too big Description CPU busy, usually resulting in high CPU usage
b: represents the number of blocked processes
swap: virtual memory size has been used, if greater than zero, indicating the machine's physical memory is not enough
free: free physical memory size
buff: system occupied by cache size (write cache)
cache: memory directly to our open files, to make the file buffer, read cache
si: read per second from disk into virtual memory size, if this value is greater than 0, indicating a shortage of physical memory
so: the size of virtual memory is written to disk per second, if this value is greater than 0, indicating a shortage of physical memory
us: user cpu time
sy: system CPU time, if the value is too high, indicating a system call, for example, frequent operation IO
id: CPU idle time, generally id + us + sy = 100
wt: IO wait CPU time
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Linux free -m command Detailed
</div><div class="article-header-box">The following display free memory is currently in use display, -m mean M bytes to display content. We take a look.
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$
free
-m
total used
free
shared buffers cached
Mem: 1002 769 232 0 62 421
-/+ buffers
/cache
: 286 715
Swap: 1153 0 1153
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The first part of the Mem line:
Total amount of memory: 1002M
amount of memory used already in use: 769m
as Free Number of free memory: 232M
Shared current has been abandoned, always 0
buffers Buffer number of cache memory: 62M
cached Page Cache amount of memory: 421M
Relationship: total (1002M) = used (769M) + free (232M)
1. vmstat view server memory, CPU and other information
Typically is accomplished by two numeric parameters, the first parameter is the sampling interval, in seconds, the second parameter is the number of samples
r: represents the run queue, if the queue is too big Description CPU busy, usually resulting in high CPU usage
b: represents the number of blocked processes
swap: virtual memory size has been used, if greater than zero, indicating the machine's physical memory is not enough
free: free physical memory size
buff: system occupied by cache size (write cache)
cache: memory directly to our open files, to make the file buffer, read cache
si: read per second from disk into virtual memory size, if this value is greater than 0, indicating a shortage of physical memory
so: the size of virtual memory is written to disk per second, if this value is greater than 0, indicating a shortage of physical memory
us: user cpu time
sy: system CPU time, if the value is too high, indicating a system call, for example, frequent operation IO
id: CPU idle time, generally id + us + sy = 100
wt: IO wait CPU time
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