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All algorithm on zram occupy same amount RAM?

Posted: 2017-08-05 09:03
by lbuiyzxl
All algorithm on zram occupy same amount RAM?
Whether should I try report this as bug to Debian BTS?
Environment:

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$ uname -a
Linux debian 4.9.0-3-686-pae #1 SMP Debian 4.9.30-2+deb9u2 (2017-06-26) i686 GNU/Linux
Test result(all " mem_used_total" field is same?):

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$ source ./curscript 
deflate
[deflate]write
536870912 bytes (537 MB, 512 MiB) copied, 14.0555 s, 38.2 MB/s
[deflate]mm_stat
536870912  3276800 16777216        0 16777216        0        0
[deflate](compacted)mm_stat
536870912  3276800 16777216        0 16777216        0        0
[deflate]read
536870912 bytes (537 MB, 512 MiB) copied, 1.72796 s, 311 MB/s
lzo
[lzo]write
536870912 bytes (537 MB, 512 MiB) copied, 2.6149 s, 205 MB/s
[lzo]mm_stat
536870912  5767168 16777216        0 16777216        0        0
[lzo](compacted)mm_stat
536870912  5767168 16777216        0 16777216        0        0
[lzo]read
536870912 bytes (537 MB, 512 MiB) copied, 1.34421 s, 399 MB/s
lz4hc
[lz4hc]write
536870912 bytes (537 MB, 512 MiB) copied, 14.5352 s, 36.9 MB/s
[lz4hc]mm_stat
536870912  3670016 16777216        0 16777216        0        0
[lz4hc](compacted)mm_stat
536870912  3670016 16777216        0 16777216        0        0
[lz4hc]read
536870912 bytes (537 MB, 512 MiB) copied, 1.54674 s, 347 MB/s
lz4
[lz4]write
536870912 bytes (537 MB, 512 MiB) copied, 2.62061 s, 205 MB/s
[lz4]mm_stat
536870912  3670016 16777216        0 16777216        0        0
[lz4](compacted)mm_stat
536870912  3670016 16777216        0 16777216        0        0
[lz4]read
536870912 bytes (537 MB, 512 MiB) copied, 1.5425 s, 348 MB/s
$ 
./curscript:

Code: Select all

test ()
{
algorithm=$1
sudo modprobe -r zram
sudo modprobe zram num_devices=1
echo ${algorithm} | sudo tee /sys/block/zram0/comp_algorithm
echo 512M |sudo tee /sys/block/zram0/disksize >/dev/null
echo \[${algorithm}\]write
yes 12 | sudo dd of=/dev/zram0 |& tail -n 1
echo \[${algorithm}\]mm_stat
cat /sys/block/zram0/mm_stat
echo 1 | sudo tee /sys/block/zram0/compact >/dev/null
echo 1 | sudo tee /proc/sys/vm/compact_memory >/dev/null
sleep 1
echo \[${algorithm}\]\(compacted\)mm_stat
cat /sys/block/zram0/mm_stat
echo \[${algorithm}\]read
sudo dd of=/dev/null if=/dev/zram0 |& tail -n 1
}

test deflate
test lzo
test lz4hc
test lz4

Re: All algorithm on zram occupy same amount RAM?

Posted: 2017-08-06 10:23
by lbuiyzxl
Maybe data in 1F is too rare than real data.
My retest result show lzo's (mem_used_total/orig_data_size) is better(smaller) than lz4.

Wed Aug 23 22:56:55 CST 2017{
Following test can't exact reproduce .
To make a reproducible test result for each algorithm,make enough memory pressure then backup your using swap device to a mirror file and use that mirror file to test your zram device for the compression result.
}
Environment:

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$ uname -a
Linux debian 4.9.0-3-686-pae #1 SMP Debian 4.9.30-2+deb9u2 (2017-06-26) i686 GNU/Linux
Retesting detail:

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$ source maxswaptest 
sudo /etc/init.d/zram stop
real	0m0.599s
sudo /etc/init.d/zram start deflate
real	0m0.111s
time ./a.out 2048 r  1 30
real	0m31.172s
[deflate]mm_stat
469659648 106177535 115027968        0 136069120     2776        8
sudo /etc/init.d/zram stop
real	0m42.506s
sudo /etc/init.d/zram start lzo
real	0m0.527s
time ./a.out 2048 r  1 30
real	0m22.937s
[lzo]mm_stat
684240896 204986478 217817088        0 237568000     3804      344
sudo /etc/init.d/zram stop
real	1m4.671s
sudo /etc/init.d/zram start lz4hc
real	0m0.364s
time ./a.out 2048 r  1 30
real	0m31.008s
[lz4hc]mm_stat
474968064 115749933 124841984        0 140357632     3621     1710
sudo /etc/init.d/zram stop
real	0m49.199s
sudo /etc/init.d/zram start lz4
real	0m0.244s
time ./a.out 2048 r  1 30
real	0m24.244s
[lz4]mm_stat
656371712 198882702 212914176        0 236359680     4013     2876
$ 
maxswaptest:

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test ()
{
echo "sudo /etc/init.d/zram stop"
(time sudo /etc/init.d/zram stop) |& grep '^real'
echo "sudo /etc/init.d/zram start $1"
(time sudo /etc/init.d/zram start $1) |& grep '^real'
echo 'time ./a.out 2048 r  1 30'
(time ./a.out 2048 r  1 30) |& grep '^real'
echo \[$1\]mm_stat
cat /sys/block/zram0/mm_stat
}
test deflate
test lzo
test lz4hc
test lz4
/etc/init.d/zram:

Code: Select all

#!/bin/sh
### BEGIN INIT INFO
# Provides:          zram
# Required-Start:    $local_fs
# Required-Stop:     $local_fs
# Default-Start:     S
# Default-Stop:      0 1 6
# Short-Description: Use compressed RAM as in-memory swap
# Description:       Use compressed RAM as in-memory swap
### END INIT INFO

# Author: Antonio Galea <antonio.galea@gmail.com>
# Thanks to Przemysław Tomczyk for suggesting swapoff parallelization
# Distributed under the GPL version 3 or above, see terms at
#      https://gnu.org/licenses/gpl-3.0.txt

FRACTION=200

MEMORY=`perl -ne'/^MemTotal:\s+(\d+)/ && print $1*1024;' </proc/meminfo`
#CPUS=`grep -c processor /proc/cpuinfo`
#swap_cache_pressure=29
#max_swap_priority=32767
#CPUS=$swap_cache_pressure
CPUS=1
SIZE=$(( MEMORY * FRACTION / 100 / CPUS ))
case "$1" in
  "start")
    echo 100 >/proc/sys/vm/swappiness
    echo 0 >/proc/sys/vm/page-cluster
    echo 0 >/proc/sys/vm/extfrag_threshold
    param=`modinfo zram|grep num_devices|cut -f2 -d:|tr -d ' '`
    modprobe zram $param=$CPUS
    for n in `seq $CPUS`; do
      i=$((n - 1))
      #echo 2 >/sys/block/zram$i/max_comp_streams
      echo $2 >/sys/block/zram$i/comp_algorithm
      echo $SIZE >/sys/block/zram$i/disksize
      mkswap /dev/zram$i
      #swapon /dev/zram$i -d -p $((max_swap_priority-i))
      swapon -p 10 /dev/zram$i
    done
    #echo 32767 >/proc/sys/vm/vfs_cache_pressure
    echo 1 >/proc/sys/vm/compact_memory
    #echo 0 >/proc/sys/vm/min_free_kbytes
    #echo 1 >/proc/sys/vm/lowmem_reserve_ratio
    #echo 0 >/proc/sys/vm/admin_reserve_kbytes
    ;;
  "stop")
    echo 60 >/proc/sys/vm/swappiness
    echo 3 >/proc/sys/vm/page-cluster
    echo 500 >/proc/sys/vm/extfrag_threshold
    #echo 100 >/proc/sys/vm/vfs_cache_pressure
    #echo 42980 >/proc/sys/vm/min_free_kbytes
    #echo 256 >/proc/sys/vm/lowmem_reserve_ratio
    #echo 8192 >/proc/sys/vm/admin_reserve_kbytes
    for n in `seq $CPUS`; do
      i=$((n - 1))
      swapoff /dev/zram$i && echo "disabled disk $n of $CPUS"
    done
    wait
    sleep .5
    modprobe -r zram
    ;;
  "compact")
    for n in `seq $CPUS`; do
      i=$((n - 1))
      echo 1 >/sys/block/zram$i/compact
    done
    echo 1 >/proc/sys/vm/compact_memory
    ;;
  *)
    echo "Usage: `basename $0` (start | stop | compact)"
    exit 1
    ;;
esac
a.out:

Code: Select all

//usage:
//indent ./a.c;gcc -O0 ./a.c
//./a.out max r/w repeat timeout

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
int
main (int argc, char **argv)
{
  time_t const start_time = time (NULL);
  time_t timeout;
  int max;
  int repeat;
  if (argc == 5)
    {
      max = atoi (argv[1]);
      repeat = atoi (argv[3]);
      timeout = ((time_t) (atoi (argv[4])));
    }
  else
    return 1;

  unsigned char **block_array =
    calloc (sizeof (unsigned char *), (size_t) (max));

  size_t block_length = (size_t) (1024u * 1024u);

  unsigned char data[3];
  data[0] = 'a';
  data[1] = 'b';
  data[2] = 'c';

  unsigned i = 0u;
  //initialize block_array
  for (i = 0u; i < max; i++)
    {
      do
	{
	  if ((timeout > ((time_t) (0)))
	      && ((time (NULL) - start_time) > timeout))
	    {
	      printf ("%u:timeouted!\n", i);
	      return 0;
	    }
	  block_array[i] = malloc (block_length);
	  if (block_array[i] != NULL)
	    {
	      unsigned bi = 0u;
	      for (bi = 0u; bi < block_length; bi++)
		block_array[i][bi] = data[bi % ((unsigned) (sizeof (data)))];
	    }
	  else
	    {
	      printf ("%u error\n", i);
	    }
	}
      while (NULL == block_array[i]);
    }
  puts ("init ok");
  unsigned score = 0u;
  if (0 == repeat)
    goto show_score;
//do page read test
  if ('r' == argv[2][0])
    for (;;)
      {
	for (i = 0u; i < max; i++)
	  {
	    if ((timeout > ((time_t) (0)))
		&& ((time (NULL) - start_time) > timeout))
	      {
		puts ("timeouted!");
		goto show_score;
	      }

	    unsigned bi = 0u;
	    for (bi = 0u; bi < block_length; bi++)
	      {
		data[bi % ((unsigned) (sizeof (data)))] = block_array[i][bi];
	      }
	    score++;
	  }
	if (repeat > 0)
	  {
	    repeat--;
	    if (0 == repeat)
	      goto show_score;
	  }
      }
//do page write test
  else if ('w' == argv[2][0])
    for (;;)
      {
	for (i = 0u; i < max; i++)
	  {
	    if ((timeout > ((time_t) (0)))
		&& ((time (NULL) - start_time) > timeout))
	      {
		puts ("timeouted!");
		goto show_score;
	      }

	    unsigned bi = 0u;
	    for (bi = 0u; bi < block_length; bi++)
	      {
		block_array[i][bi] = data[bi % ((unsigned) (sizeof (data)))];
	      }
	    score++;
	  }
	if (repeat > 0)
	  {
	    repeat--;
	    if (0 == repeat)
	      goto show_score;
	  }
      }
show_score:
  printf ("score:%u\n", score);
  return 0;
}