How to quickly check RAM on Linux

If you suspect that RAM in your server is corrupted (for example, if you see "wrong record length" errors frequently), you can use the following way to quickly check the memory with the following commands:

dd if=/dev/zero of=/run/zero.bin bs=1G count=8
sha1sum /run/zero.bin

The first command creates 1 file 8Gb in size with zeroes, the second command calculates the checksum for this file.
Specify parameters to cover almost all RAM and run these commands 5-7 times, and compare the results - all checksums should be identical.
If they are different, with high chances your RAM is corrupted - in this case, run more thorough tests with memtest86 tool or with memtester.