How to read the dCache Statistics

The dCache statistic pages allow an insight into the distribution of the different storage classes among the dCache pools and the amount of data flowing into the pools from the HSM as well as the amount of data fetched by the clients from the pools. The numbers are calculated per day from midnight to midnight, except for the most recent day where we compare midnight against the the last full hour. For each day we provide the total amount of data at the beginning of the day, at its end (midnight), the data which has been flown into the pools from the HSM and the amount which has been fetched by the clients. This numbers are given for all pools, for all storage classes, for all storage classes within each pool and for all pools occupied by a specified storage class as well as the total daily amount for all pools and storage classes.

A typical table is given below. Each table entry corresponds to a day, a storage class or a pool. (Here denoted a <key>). An entry uses three different ways to represent the four different values described above. The values and colors are :

The display methods are :
<key> Absolute Values Data / MBytes Relative Values
<key> 8383832 + 432732
8430822
1951231
day/pool name/storage class name
Data when day began Data added by HSM .
8383832 + 432732
Data when day ended .
8430822
Data taken by client .
1951231