Despite being quiet on this, we have not solved the problem. We have: * Tried other file systems (e.g., ext4) * Tried faster "server-grade" SATA disks. * Tried SATA3 interface as well as SATA2. The same thing happens. Periodically, write calls are blocking for 4-5 seconds instead of the usual 20-30 msecs. I have seen one unexpected thing: when running xosview during all this, the MEM usage shows the cache use slowly growing. The machine has 32 GB of RAM. The cache use just grows and grows as file file system is written to. Here is the part I don't get: * If I close all apps that have a file open on the file system, the cache use remains. * If I run the 'sync(1)' command, the cache use remains. I would have thought that the cache would be freed as there is nothing left to cache. If not immediately, over a decent amount of time. But this is not the case. * Only when I unmount the file system does the cache get freed. Immediately. Why would the cache grow and grow? Since the delay, when it happens, grows and grows, I get the feeling that this file system cache in RAM is slowly getting bigger and bigger, and each time it needs to be flushed, it takes longer and longer. If the cache is being emptied at some reasonable point, why would it continue to grow? Remember that for each mounted file system there is one process writing to a single file. The disk usage remains 100% constant in terms of what is sent to be written. Is there some policy or setting that controls how the file system deals with file system cache in RAM? More specifically, is there any way to limit it's size for a file system? Is there a way to see how much of the RAM cache for a file system is actually containing data waiting to be flushed? I have seen some reports that using O_SYNC when opening the file makes the write times more even. I guess I could open() a wile with this, and then fdopen() it. fcntl() seems not to support O_SYNC... Yours sincerely, Roger Oberholtzer Ramböll RST / Systems Office: Int +46 10-615 60 20 Mobile: Int +46 70-815 1696 roger.oberholtzer@ramboll.se ________________________________________ Ramböll Sverige AB Krukmakargatan 21 P.O. Box 17009 SE-104 62 Stockholm, Sweden www.rambollrst.se -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org