On my system,
sar reports an average write to disk about 5MB/s. Using
dstat I found that it's not so permanently, but there are peaks to 30-50MB/s, and then are sleeps.
iotop i found that most of writing is done by one application (but i don't know how sure it's).
fatrace I saw that application opening, creating files in different directories, and then close/remove them. There are many files, but I didn't see in
strace much writing. I try to find out more using
/proc/pid/fd to see if there are any files constantly incremented (logs, etc) but I couldn't find any. So my conclusion is that all writing is done with small temporary files created by application.
How do I check how much is written to each file? I would like to have a report with the amount of bytes written to each file.
Is there any way to do it? I thought about rewriting syscalls like
write to monitor changes to every file, or using
systemtap but i hope that there is simpler way.