Hello Anssi,
Generally speaking you can follow the recommendations for sizing iMC here: https://support.hpe.com/hpesc/public/docDisplay?docId=a00075913en_us
Database sizing can be done based on the sizing of your iMC server + modules and deployment scheme. I would give the DB similar specs as the ones given to the iMC system, and then monitor the load and reduce or increase the hardware as needed.
Keep in mind that your requirements may also vary depending on other factors... especially if you use a shared database server and iMC's DB is just using one instance on the server. Then you'd obviously have higher requirements for the server considering the other apps that are using database instances there too.
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Justin Guse
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