22f4db4b0e
Changed used memory calculation to account for shared memory in accordance with this: https://github.com/KittyKatt/screenFetch/issues/386#issuecomment-249312716
94 lines
3.2 KiB
C++
94 lines
3.2 KiB
C++
/* vim: tabstop=2 shiftwidth=2 expandtab textwidth=80 linebreak wrap
|
|
*
|
|
* Copyright 2012 Matthew McCormick
|
|
* Copyright 2015 Pawel 'l0ner' Soltys
|
|
*
|
|
* Licensed under the Apache License, Version 2.0 (the "License");
|
|
* you may not use this file except in compliance with the License.
|
|
* You may obtain a copy of the License at
|
|
*
|
|
* http://www.apache.org/licenses/LICENSE-2.0
|
|
*
|
|
* Unless required by applicable law or agreed to in writing, software
|
|
* distributed under the License is distributed on an "AS IS" BASIS,
|
|
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
* See the License for the specific language governing permissions and
|
|
* limitations under the License.
|
|
*/
|
|
|
|
#include <sstream>
|
|
#include <fstream>
|
|
#include <sys/sysinfo.h>
|
|
|
|
#include "memory.h"
|
|
#include "conversions.h"
|
|
|
|
void mem_status( MemoryStatus & status )
|
|
{
|
|
std::string line;
|
|
std::string substr;
|
|
size_t substr_start;
|
|
size_t substr_len;
|
|
|
|
unsigned int total_mem;
|
|
unsigned int used_mem;
|
|
|
|
/* Since linux uses some RAM for disk caching, the actuall used ram is lower
|
|
* than what sysinfo(), top or free reports. htop reports the usage in a
|
|
* correct way. The memory used for caching doesn't count as used, since it
|
|
* can be freed in any moment. Usually it hapens automatically, when an
|
|
* application requests memory.
|
|
* In order to calculate the ram that's actually used we need to use the
|
|
* following formula:
|
|
* total_ram + shmem - free_ram - buffered_ram - cached_ram - srclaimable
|
|
*
|
|
* example data, junk removed, with comments added:
|
|
*
|
|
* MemTotal: 61768 kB old
|
|
* MemFree: 1436 kB old
|
|
* MemAvailable ????? kB ??
|
|
* MemShared: 0 kB old (now always zero; not calculated)
|
|
* Buffers: 1312 kB old
|
|
* Cached: 20932 kB old
|
|
* SwapTotal: 122580 kB old
|
|
* SwapFree: 60352 kB old
|
|
*/
|
|
|
|
std::ifstream memory_info("/proc/meminfo");
|
|
|
|
while( std::getline( memory_info, line ) )
|
|
{
|
|
substr_start = 0;
|
|
substr_len = line.find_first_of( ':' );
|
|
substr = line.substr( substr_start, substr_len );
|
|
substr_start = line.find_first_not_of( " ", substr_len + 1 );
|
|
substr_len = line.find_first_of( 'k' ) - substr_start;
|
|
if( substr.compare( "MemTotal" ) == 0 )
|
|
{
|
|
// get total memory
|
|
total_mem = stoi( line.substr( substr_start, substr_len ) );
|
|
}
|
|
else if( substr.compare( "MemFree" ) == 0 )
|
|
{
|
|
used_mem = total_mem - stoi( line.substr( substr_start, substr_len ) );
|
|
}
|
|
else if( substr.compare( "Shmem" ) == 0 )
|
|
{
|
|
used_mem += stoi( line.substr( substr_start, substr_len ) );
|
|
}
|
|
else if( substr.compare( "Buffers" ) == 0 ||
|
|
substr.compare( "Cached" ) == 0 ||
|
|
substr.compare( "SReclaimable" ) == 0 )
|
|
{
|
|
used_mem -= stoi( line.substr( substr_start, substr_len ) );
|
|
}
|
|
}
|
|
|
|
// we want megabytes on output, but since the values already come as
|
|
// kilobytes we need to divide them by 1024 only once, thus we use
|
|
// KILOBYTES
|
|
status.used_mem = convert_unit(static_cast< float >( used_mem ), MEGABYTES, KILOBYTES);
|
|
status.total_mem = convert_unit(static_cast< float >( total_mem ), MEGABYTES, KILOBYTES);
|
|
}
|
|
|