Much less available memory than should be

Hello,

on some of our PCs we have little available and we don't know why. The sum of memory of all processes in top is much less than used memory (sum is less than 50%, used is about 80%) and according /proc/meminfo the kernel is also not using that much memory.

We also compared /proc/meminfo with another PC (can be found, where we are running mostly the same stuff and don't have this problem. All values are lower or only slightly higher than on the problematic PC, however the there is a difference of 800MB in used memory. After a restart (after one hard reset the PC did not boot, but this might be for some different reasons) the memory usage was normal again.
We are using the integrated Intel GPU, I'm not sure how this affects the memory usage but the GPU memory usage should be approximately the same on both PCs.

Here the comparison of /proc/meminfo (first numbers are from the problematic PC, second numbers from the other PC):
Code:bad PC good PC
MemTotal: 3893868 kB MemTotal: 3893868 kB
MemFree: 128020 kB MemFree: 160220 kB
MemAvailable: 425044 kB MemAvailable: 1167016 kB
Buffers: 83072 kB Buffers: 333928 kB
Cached: 344508 kB Cached: 776344 kB
SwapCached: 12136 kB SwapCached: 8920 kB
Active: 1714676 kB Active: 2088328 kB
Inactive: 664428 kB Inactive: 1220148 kB
Active(anon): 1455244 kB Active(anon): 1523848 kB
Inactive(anon): 496648 kB Inactive(anon): 666312 kB
Active(file): 259432 kB Active(file): 564480 kB
Inactive(file): 167780 kB Inactive(file): 553836 kB
Unevictable: 268 kB Unevictable: 268 kB
Mlocked: 32 kB Mlocked: 32 kB
SwapTotal: 1951740 kB SwapTotal: 1951740 kB
SwapFree: 1497852 kB SwapFree: 1737980 kB
Dirty: 308 kB Dirty: 468 kB
Writeback: 0 kB Writeback: 0 kB
AnonPages: 1946936 kB AnonPages: 2196080 kB
Mapped: 127492 kB Mapped: 192320 kB
Shmem: 2156 kB Shmem: 3284 kB
KReclaimable: 156788 kB KReclaimable: 181536 kB
Slab: 372824 kB Slab: 309404 kB
SReclaimable: 156788 kB SReclaimable: 181536 kB
SUnreclaim: 216036 kB SUnreclaim: 127868 kB
KernelStack: 15216 kB KernelStack: 14656 kB
PageTables: 14816 kB PageTables: 15644 kB
NFS_Unstable: 0 kB NFS_Unstable: 0 kB
Bounce: 0 kB Bounce: 0 kB
WritebackTmp: 0 kB WritebackTmp: 0 kB
CommitLimit: 3898672 kB CommitLimit: 3898672 kB
Committed_AS: 6078024 kB Committed_AS: 7755840 kB
VmallocTotal: 34359738367 kB VmallocTotal: 34359738367 kB
VmallocUsed: 30288 kB VmallocUsed: 29700 kB
VmallocChunk: 0 kB VmallocChunk: 0 kB
Percpu: 4704 kB Percpu: 3808 kB
HardwareCorrupted: 0 kB HardwareCorrupted: 0 kB
AnonHugePages: 0 kB AnonHugePages: 0 kB
ShmemHugePages: 0 kB ShmemHugePages: 0 kB
ShmemPmdMapped: 0 kB ShmemPmdMapped: 0 kB
FileHugePages: 0 kB FileHugePages: 0 kB
FilePmdMapped: 0 kB FilePmdMapped: 0 kB
CmaTotal: 0 kB CmaTotal: 0 kB
CmaFree: 0 kB CmaFree: 0 kB
HugePages_Total: 0 HugePages_Total: 0
HugePages_Free: 0 HugePages_Free: 0
HugePages_Rsvd: 0 HugePages_Rsvd: 0
HugePages_Surp: 0 HugePages_Surp: 0
Hugepagesize: 2048 kB Hugepagesize: 2048 kB
Hugetlb: 0 kB Hugetlb: 0 kB
DirectMap4k: 1020676 kB DirectMap4k: 707332 kB
DirectMap2M: 3037184 kB DirectMap2M: 3350528 kB
DirectMap1G: 0 kB DirectMap1G: 0 kBHere are the outputs of "cat /proc/meminfo", "ps aux --sort -rss" (processes with >0.1% memory usage) and "free", each for the problematic PC (*_bad) and the other PC (*_good), free is in one file because of file number limit.
Attachment 36955
Attachment 36956
Attachment 36957
Attachment 36958
Attachment 36959

Does anyone know what is using those missing 800MB of memory?

Thanks
Thomas
Attached Files

	meminfo_bad.txt (1.4 KB)
	meminfo_good.txt (1.4 KB)
	psaux_bad.txt (1.9 KB)
	psaux_good.txt (2.1 KB)
	free.txt (425 Bytes)