only cache populated samples
only cache populated samples

tcspain/SynchWeb,tcspain/SynchWeb,DiamondLightSource/SynchWeb,tcspain/SynchWeb,tcspain/SynchWeb,DiamondLightSource/SynchWeb,DiamondLightSource/SynchWeb,DiamondLightSource/SynchWeb,DiamondLightSource/SynchWeb,tcspain/SynchWeb,DiamondLightSource/SynchWeb,tcspain/SynchWeb