Sizing

T-Shirt Sizing Technique

This sizing technique uses t-shirt sizes (XS, S, M, L, XL) under the assumption that having an estimate is better than none. It can be useful for the budget planning phase even when figures may not be clear, assumptions can be made and validation can occur later.

Figure 1: T-Shirt Sizing

Now, think of these t-shirt sizes as hardware requirements where XS requires the least amount of power/memory/etc. and XL requires the most.

Figure 2: Hardware T-Shirt Sizing Equivalent

IT-Conductor Sizing Table

To make things much easier, we came up with the IT-Conductor Sizing Table based on the T-Shirt Sizing principle to guide you in your sizing exercise.

T-Shirt Size	CPU (Core)	Memory (Gb)	Landscape (System)
XS	4	4	<=25
S	4	8	<=50
M	4	12	<=75
L	8	16	<=100
XL	8	32	>100

IT-Conductor Production Gateway should have a standby/failover Gateway VM of the same size to ensure service resiliency and meet IT-Conductor Service Level Agreement requirements.

Note: The rule of thumb is 25 systems per 4CPU 4GB. Then add 4GB memory for the next 25 systems. CPU is not usually a constraint.