Server is down after changing machine type in Google Cloud Platform

I changed my machine type(GCP) by stopping the instance, after increasing the machine type I restarted the instance and now server stopped working, the website is down now.
Upgraded from 1 vCPU, 1.7 GB memory to 2 vCPU, 4GB memory.
And if I select other than 1 vCPU, 1.7 GB memory, the webserver doesn’t respond.
Also, I can’t access SSH from a web browser it gives me an error that “Connection Failed. We are unable to connect to the VM on port 22.”

Log: https://pastebin.pl/view/2af02149

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Author: Sandeep Kumar Giri

LDAP + SAMBA problems

After setting up my openldap on centos 7 i got a problem while integrating samba !
i followed the steps of many tuto :
exemple : https://admin.shamot.cz/?p=470
but i found a problem while taping that command :
net getlocalsid
i got an error :
ailed to bind to server ldap://172.16.0.180 with dn=”cn=ldapadm” Error: Invalid credentials
(unknown)
pdb_init_ldapsam: WARNING: Could not get domain info, nor add one to the domain. We cannot work reliably without it.
pdb backend ldapsam:ldap://172.16.0.180 did not correctly init (error was NT_STATUS_CANT_ACCESS_DOMAIN_INFO)
WARNING: Could not open passdb

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Author: Bruce

Slab SReclaimable memory can not be recycled?

CentOS Linux release 7.2.1511 (Core)

Linux version 3.10.0-514.26.2.el7.x86_64 (builder@kbuilder.dev.centos.org) (gcc version 4.8.5 20150623 (Red Hat 4.8.5-11) (GCC) ) #1 SMP TueJul 4 15:04:05 UTC 2017

/proc/meminfo:

MemTotal:       16267428 kB
MemFree:          237816 kB
MemAvailable:    7501712 kB
Buffers:           18076 kB
Cached:           745340 kB
SwapCached:            0 kB
Active:          5015316 kB
Inactive:         152100 kB
Active(anon):    4404088 kB
Inactive(anon):      972 kB
Active(file):     611228 kB
Inactive(file):   151128 kB
Unevictable:           0 kB
Mlocked:               0 kB
SwapTotal:             0 kB
SwapFree:              0 kB
Dirty:              1928 kB
Writeback:             0 kB
AnonPages:       4404052 kB
Mapped:            36320 kB
Shmem:              1008 kB
Slab:           10579260 kB
SReclaimable:    6839864 kB
SUnreclaim:      3739396 kB
KernelStack:       19232 kB
PageTables:        25760 kB
NFS_Unstable:          0 kB
Bounce:                0 kB
WritebackTmp:          0 kB
CommitLimit:     8133712 kB
Committed_AS:    7992196 kB
VmallocTotal:   34359738367 kB
VmallocUsed:       94920 kB
VmallocChunk:   34359635708 kB
HardwareCorrupted:     0 kB
AnonHugePages:   2297856 kB
HugePages_Total:       0
HugePages_Free:        0
HugePages_Rsvd:        0
HugePages_Surp:        0
Hugepagesize:       2048 kB
DirectMap4k:      161664 kB
DirectMap2M:    10323968 kB
DirectMap1G:     8388608 kB

slabtop:

 Active / Total Objects (% used)    : 18223363 / 42966058 (42.4%)
 Active / Total Slabs (% used)      : 1183671 / 1183671 (100.0%)
 Active / Total Caches (% used)     : 73 / 95 (76.8%)
 Active / Total Size (% used)       : 4513721.33K / 10427564.51K (43.3%)
 Minimum / Average / Maximum Object : 0.01K / 0.24K / 8.00K

  OBJS ACTIVE  USE OBJ SIZE  SLABS OBJ/SLAB CACHE SIZE NAME
6763716 6763212  99%    0.11K 187881       36    751524K sysfs_dir_cache
5604032 949314  16%    0.06K  87563       64    350252K kmalloc-64
4202094  67116   1%    0.04K  41197      102    164788K ext4_extent_status
3893484 2373049  60%    0.19K 185404       21    741616K dentry
3748191 1802716  48%    0.58K 138832       27   2221312K inode_cache
3251724 987321  30%    0.09K  77422       42    309688K kmalloc-96
2611301 1924963  73%    0.57K  93416       28   1494656K radix_tree_node
2590224 764829  29%    0.10K  66416       39    265664K buffer_head
2042465 284009  13%    0.05K  24029       85     96116K shared_policy_node
1802221 613054  34%    1.01K  58287       31   1865184K ext4_inode_cache
1263674 182269  14%    0.31K  50548       25    404384K nf_conntrack_ffffffff81aa0e80
1251789 210295  16%    0.19K  59609       21    238436K kmalloc-192
726016 686721  94%    0.03K   5672      128     22688K kmalloc-32
712992   9160   1%    0.50K  22281       32    356496K kmalloc-512
591360  43401   7%    0.12K  18480       32     73920K kmalloc-128
579564   4356   0%    0.11K  16099       36     64396K jbd2_journal_head
310514   4893   1%    2.00K  19576       16    626432K kmalloc-2048
183680 181248  98%    0.06K   2870       64     11480K kmem_cache_node
181936 180969  99%    0.25K   5686       32     45488K kmem_cache
130254   1632   1%    0.04K   1277      102      5108K Acpi-Namespace
 84512  19793  23%    1.00K   2641       32     84512K kmalloc-1024
 83312   2464   2%    0.25K   2608       32     20864K dquot
 80224  12022  14%    0.25K   2574       32     20592K kmalloc-256
 53538   2009   3%    1.94K   3347       16    107104K TCP
 39490  15690  39%    4.00K   5106        8    163392K kmalloc-4096
 28800    860   2%    1.56K   1440       20     46080K mm_struct
 23808  20992  88%    0.02K     93      256       372K kmalloc-16

To the problem:

I running some docker containers on this host, set mem limit about 13g(5g actually used). I want to start another java process, but killed by oom killer. SReclaimable of Slab can not be freed.

Things I tried

echo 3 > /proc/sys/vm/drop_caches

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Author: nuaa_tiger