[LU-17722] wait_delete_completed() to trim underlying fs backed by tmpfs

• Type: Improvement
• Resolution: Unresolved
• Priority: Minor
• Severity: 3
• Assignee: WC Triage
• Reporter: Alex Zhuravlev

Description

when a test runs on devices stored in /tmp (tmpfs) it consumes ram and consumed memory is never released even if corresponding filesystem stores zero data. this way testing consume more memory than needed really.
it's possible to release such an unused memory. for example, in wait_delete_completed()