A couple of years ago I had a problem where a program was streaming data to a file. Unfortunately, the OS cached the contents in RAM and only dealt with it occasionally. The problem was that this would cause periodic delays of a long time while the cache was dealt with. Write calls would have to wait until this task was completed. See the following for the original discussion: https://lists.opensuse.org/opensuse/2013-06/msg00069.html The solution that worked was to have something like the following running: while [ 1 ]; do sync; echo 1 > /proc/sys/vm/drop_caches; sleep 60; done & This really did solve the problem. We have now updated the OS for this system to Leap 42.3. It does not seem that this is having the same effect. One difference I see is that the sync command seems to take a very long time. Like over a minute each time. The fwrite() calls change from taking 1 msec to write a buffer (which is actually cached in ram by the kernel fs driver until later), to 20 secs or a minute. While we do buffer data, these long write delays are a problem. I have looked to see if there is anything different about /proc/sys/vm/drop_caches since we had originally used it. I think it was openSUSE 13.1 where we last saw that it seemed to be working as expected. Anyone have a clue about this? Maybe there is a better way to do this now? We are using ext4. IIRC, we tried other file systems at the time, but this was a general feature of all file systems. -- Roger Oberholtzer -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org