Script To Get the Report Execution log, ex. timetaken .

declare 
@ReportName nvarchar(425) 
, @ReportPath nvarchar(425)
, @ReportId uniqueIdentifier


set @ReportName = 'your report name'
set @ReportPath = '/' + 'your folder name' 


if(@ReportName is null) 
set @ReportName = ''
if(@ReportPath is null)
set @ReportPath = ''


select 
c.[Name],
el.InstanceName, el.TimeEnd - el.TimeStart, 
el.TimeDataRetrieval, el.TimeProcessing, el.TimeRendering, el.Status, el.ByteCount, el.[RowCount]
from 
[ReportServer].[dbo].catalog c inner join [ReportServer].[dbo].ExecutionLog el on c.ItemID = el.ReportId
where 
c.[Name] like @ReportName + '%'
and c.path like @ReportPath + '%'
order by 
TimeEnd desc
GO