RHEL7 hugeadm:WARNING: failed to set pool minimum to 120000 became 87044

Tried to size up hugepage by sysctl but look into meminfo no change:

# sysctl -w vm.nr_hugepages=120000
# grep HugePage /proc/meminfo                 
AnonHugePages:         0 kB
HugePages_Total:   88700
HugePages_Free:     6674
HugePages_Rsvd:     5018
HugePages_Surp:        0

Try with hugeadm, error “failed to set pool”:

# hugeadm --list-all-mounts
# hugeadm --pool-list
# hugeadm --pool-pages-min 2MB:120000
hugeadm:WARNING: failed to set pool minimum to 120000 became 87044

Solution:

Many articles ask for reboot to fix, finally find a way to modify online:

use drop_caches, then modify by hugeadm again, monitor from another session can see HugePage increasing.

# sync; echo 3 > /proc/sys/vm/drop_caches
# hugeadm --pool-pages-min 2MB:120000

$ watch hugeadm --pool-list

Reference:

• https://datahunter.org/hugepages
• https://medium.com/hungys-blog/clear-linux-memory-cache-manually-90bec95ea003

Azure Synapse Workspace SQL Pool “Cannot connect to SQL Database” “Login failed for user ”.”

To utilize the Synapse Workspace native database as datawarehouse, we need to first create sql pool (not the “SQL on-demond”)

After creation complete, we need to refresh (Ctrl + F5) the browser or relogin into Synapse Workspace. Then we can see the new created SQL pool automatically appear as a data store.

However, if you select it as Source or Destination, it throws error below:

Cannot connect to SQL Database: ‘tcp:xxx.sql.azuresynapse.net,1433’, Database: ‘testdb’, User: ”. Check the linked service configuration is correct, and make sure the SQL Database firewall allows the integration runtime to access. Login failed for user ”., SqlErrorNumber=18456,Class=14,State=1, . Activity ID: xxx

Solution:

While tried to create a support ticket for this issue. Finally we get the hint:

Known issues
…
Creation of a new SQL pool operation might appear to have failed if your workspace name starts with a number. However, SQL pool is created successfully, the GRANT control setting would not have been applied correctly in this scenario. You need to follow the below steps to have the proper “Grant CONTROL” setting applied manually to your newly created SQL pools:
Click on “Launch Synapse Studio” in the portal
Click Data in the Left Navigation Panel and navigate to the SQL Pool that needs the setting in the Databases section
Invoke a “New SQL Script” on the SQL Pool
To create a new workspace managed identity user and to assign control permissions to the user run the following in the pool: CREATE USER [WorkspaceName] FROM EXTERNAL PROVIDER GRANT CONTROL TO [WorkspaceName]
…

After following the instruction, we able to connect the new SQL pool.