Issue

• When the customer does rman backups (on veritas filesystem) and some sql queries (in databases ontop of veritas filesystem), The "kmalloc-1024" buffer (part of "cat /proc/slabinfo" output) grows until the system has no memory left. So under usage the buffer constantly grows, and after some weeks memory is used up.
• The issue is seen on multiple systems.
• The kmalloc-1024 cache only seems to grow with pread and pwrite.
• Memory is not shrinking when veritas filesystems are umounted.
• Unloading the veritas modules is not possible
• Dropping caches using /proc/sys/vm/drop_caches does not influence that memory.
• "-/+ buffers/cache" in the "free" output is decreasing when the filesystem is used and kmalloc-1024 is growing.
• Simpler tools like dd, cp, tar etc. were not able to reproduce the issue.
• Normal tools like cp, tar etc. use read/write. Tools like rman use "pread" and "pwrite", these seem to cause the issue