Most commonly used IT Jargons

Rolling restart-A way of restarting multiple servers from cluster one by one.

Throughput- Number of Request processed/second
Concurrency-Throughput* response time

Horizontal Scaling: Here scaling happens by adding new m/c into our pool of resources.
Vertical Scaling: We scale by adding more power  (CPU/RAM)to an existing machine.
TTL: Time to live time lifespan of a data
Shards: Splitted into smaller groups.Eg In Elastic search indexes are splitted into shards 1 index->5 shards
Primary/Replica: If you have m primaries and n replicas, you require m*(n+1) data nodes
CNAME:Maps a name to another name. Records in DNS used to specify a domain name is an alias for another domain name.
Cascading effect: Unforeseen chain of  events due to an act affecting a system

Git: cheat notes

Git : helpful commands: 

1. Undo local commit to master
I.
git checkout master
git reset --soft head~

Or

git log --oneline

git reset commit#id#hash

#

git revert <revert_id> --no-edit

Or git reset HEAD~  
2. git tagging

git tag <tag_name> commit_id

git push origin --tags

git checkout -b branch_name tag_name

3. Cherry Pick:

Get the the merged commit SHA id

[after checking out the release branch

git cherry-pick -m 1 <<merged SHA ID>>

git status

git push

4. Checkout remote branch

git fetch

git checkout REMOTE_BRANCH

5. Git revert local commit to master

git reset --hard origin/master     

6. Git checkout remote branch

 git fetch  

 git branch -v -a 

 git switch new_branch_name 

 

 git pull origin master 

 git config pull.rebase false   

 git push  

6. Git checkout a commitid

git checkout #commitId/commit-id-sha#

7. Git checkout from  specific commitid on a new branch

git checkout -b <new-branch-name> <commit-id-sha>

How to quickly create a Sequence diagram

Here we will see how to quickly create sequence diagram for a given code flow.

Remember a Sequence diagram shows how object interaction arranged in time sequence. 

ClassA->ClassB:methodInA

loop iterates over multiple creator

ClassB->ClassC:methodInB

ClassC->ClassD:methodInC

ClassD->ClassC:returns some VOs

end

loop invokes other processors

ClassB->ClassE:processData

end

note left of ClassE: Application cache is ready