Disk filling up until a reboot

Dani Avni 0 Reputation points

I have a VM running in ESXi with Windows Server 2019 running some application that writes data to drive Z (not the system disk, NTFS, 500GB capacity).

When looking in disk properties I see the disk has 50GB free but when summing up the file sizes on the disk, they sum to 407.5GB allocated (505.2 total size - some folders are compressed).. Because 407GB is allocated I should have about 90GB free but I only see 50GB. When I restart the server, the disk space returns to normal and I have 90Gb free and it starts to shrink again.

I thought about VSS but running


says that 0 bytes are allocated on drive Z

I also checked with TreeSize (ran as admin) and the total allocated disk is 407.5GB

I also tried using Nirsoft Alternate Data Stream viewer to make sure no app is holding some data but nothing comes up.

Apart from rebooting the server every night to free the disk space, What am I missing? Could it be related to the fact that some folders are compressed?

Windows Server 2019
Windows Server 2019
A Microsoft server operating system that supports enterprise-level management updated to data storage.
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  1. Limitless Technology 43,916 Reputation points


    Thank you for your question and reaching out. I can understand you are having query\issues related to Disk space.

    1. Please verify and check if there is Data Deduplication is On on this Drive ?
    2. Please check if there are any Other services or applications Data are stored on that Drive.
    3. Please check and move if there are any pagefiles are saved on that volume.

    --If the reply is helpful, please Upvote and Accept as answer--

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