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Good Evening SCNers,
thought of the day, what does SAP HANA have in common with an old car ?
Let’s put it another way, what does a regular modern family car have that SAP HANA does not have ?
Read on and find out.
My first car, when I started driving it in 1990, was already thirty years old ! It could be started with a handle on the front.
The petrol gauge. We all know this from cars old and new, every car has a fuel (or petrol) gauge.
The petrol gauge, even in a new car does not do much, all the petrol gauge tells us is how much petrol we have left at any point of time.
This is how the petrol gauge looked in older cars:
and this is how the petrol gauge looks on modern cars:
In the last 60 years the car petrol gauge has not changed very much has it, it still
does the same simple task, telling the Driver (the Administrator) at any point in time how much petrol capacity is left.
In the old days, in a car with only the petrol gauge to work with, the Driver (Administrator) of the car had to use experience and knowledge to try to understand,
from the available remaining petrol(let’s call this capacity), and based upon the current driving style (let’s call this usage),
just how far could the car continue being driven until it would run out of petrol (capacity to continue) ?
And then, the Administrator (Driver) had to figure out where and when to take petrol (get more capacity), to get more petrol capacity before the car would run out of petrol. In which case the car would cease to function and the Administrator (Driver) would have to walk along the road with a can of petrol.
And this was not an uncommon sight in the past and still happens to some people today.
So what does this have to do with SAP HANA ?
In the days before the InMemory databases, if a database ran out of capacity (disk), a Unix
Administrator could just run a few commands and voila there would be more disk space, more
capacity for the database. Consequently, capacity monitoring in disk based databases was set
to generate alerts at 30% capacity remaining available, 20% capacity remaining available, 10% capacity remaining available,
with each threshold of remaining available capacity there was enough time to extend the disk space.
This is similar to cars in the 90’s giving a red light is the petrol tank was running low on fuel
as an alert for the Driver (Administrator) to take more fuel.
In the days of disk based databases we didn’t need to know so much how fast the database
was growing because we were able to add more disk capacity so easily and quickly.
Now back to SAP HANA.
In the SAP HANA world:
. capacity is Memory/RAM
. and Memory/RAM is not like disk space,Memory/RAM is made up of blocks or Server Nodes and therefore to a certain extent much more finite than Disk
. And more worryingly, extending Memory/RAM or ServerNodes is not as quick and easy as extending disk space and for ServerNodes if new ones need to be purchased can have a lead time of months !
And so in the SAP HANA world, we need to understand:
. how much remaining memory capacity we have available – the classic old fashioned car petrol gauge
. our current memory usage rate based upon historical growth patterns – how much memory are we consuming per month, gb/month
. from the above two items, for how many months at the current growth rate gb/month we can run before we run out of petrol/memory
. since we know how long it will take to add more memory capacity, either memory modules or more nodes, at what point in time do we need to trigger the order for capacity based upon the current usage, capacity left, and growth rate ?
. And then try to figure out that lot with Multiple Tenants which have different usage and growth rates
But we don’t have any tools from SAP to do this ! Yes we have the HANA 2.0 Cockpit but it is too little.
The modern car dashboard
These parameters, these days are pretty much standard equipment in modern family cars, we have:
. The petrol gauge telling us how much petrol we have left
. The analytics telling us based upon historic usage analysis of the driving style, what the current usage is in litres/100km or miles/gallon
. The predictive analytics telling us based upon the current usage style and historic consumption how far we can drive before we will run out of petrol
It looks like this:
and then, one step further, if we are really lucky we have a navigation system connected to the predictive analytics which will tell us where the next petrol station is within range of our petrol capacity:
So what does SAP HANA have in common with an old car, with SAP HANA today the Administrator is pretty much working with only the fuel gauge to understand how much available memory capacity there is in the HANA system.
We need SAP to get the SAP HANA Administrator tools to the same standard as we have come to take for granted in modern cars.
We need a dashboard which tells us:
. How much available memory capacity there is today at a Node level and across all Nodes
. What the current memory consumption rate is by Tenant, by Node and across all Nodes,based upon historical growth from the last months in GB/Month
. We need to know at the current consumption rate when Individual Nodes and across Nodes the HANA System will be out of capacity, at the current consumption rate in GB/Month, for how many more months can we run before we hit the wall
. We need to be able to tell the dashboard how long it will take to procure more capacity so that the dashboard can Alert us trigger the procurement of more capacity within time – like in the car when the car goes beep and says you need to take more fuel within 90kms
. And the cherry on the top, wouldn’t it be nice if the SAP HANA System gave us recommendations on the layout of the Tenants across the ScaleOut Server Nodes, where to put which Column and Row Stores to get the optimum utilization of the available HANA Capacity across the Nodes
. And the second cherry would be, you remember this blog about SAP HANA Tenant Mobility well imagine if the dashboard had a view of all of our Production (or whatever layer of the landscape) MDC enabled HANA Systems and could give us recommendations which Tenants to combine and host together and where based upon usage rates and growth rates, how cool would that be
Managing growth and capacity in the disk based database world was really easy peasy.Today in the in-memory database world managing growth and available capacity needs a lot more thought and has infact become a science.
What are we doing, we’ve developed complex Excels and are using those as our predictive analytics dashboards, because so far the tools from SAP haven’t provided what we are looking for.
Dear SAP please have a think about the above and see if it would be possible in future generations of the SAP HANA product to have these Administrator features.
Whatta you think ?
p.s. there will be a special kudos if you can figure out which car the modern dashboard photos are taken from