Bernd Wollny <wiloyee <at> gmail.com> writes: > > Hello, > can some one explain why Despooling shows a different size then > "Bytes Written"? > > Committing spooled data to Volume "000129". Despooling 6,113,782,150,893 bytes ... > Sending spooled attrs to the Director. Despooling 23,036,553 bytes ... > > FD Bytes Written: 6,108,098,611,694 (6.108 TB) > SD Bytes Written: 6,108,113,808,309 (6.108 TB) > > SD Bytes > FD Bytes Padding ??? > > Despooling > SD Bytes Why ??? >
I have not all details at hand but it looks alright. It all comes down to the encapsulation of the data at different levels. The FD send the data as chunks of 64 Kb to the SD with some meta data like filenumber and stream type. The SD encapsulated those into so called RECORDs which contain the stream type and some other meta data and the actual payload the FD send. Those RECORDs are then serialized in blocks which are checksummed. How many records fit in a block depends on the blocksize you set on the device (or in the pool.) if a RECORD only fits partly the rest will be in the next block as a so called continuation RECORD. There also some extra session related data in the volume blocks like start of session end of session etc. So what you see is FD writes x bytes which is more or less what it read from your backup filesystem without any metadata. SD writes that data with some more metadata into blocks which are check-summed and might have some overflow information. The spooling and despooling amounts are the actual serialized data that end up on your volume (disk or tape) as the spool file is essentially the same data already serialized on despooling this is just copied from the spool area to the "real" volume. The whole idea of spooling is only to do the serialization already to a disk file so on despooling to lets say tape we can write things at full speed. -- Marco van Wieringen [email protected] Bareos GmbH & Co. KG Phone: +49-221-63069389 http://www.bareos.com Sitz der Gesellschaft: Köln | Amtsgericht Köln: HRA 29646 Komplementär: Bareos Verwaltungs-GmbH Geschäftsführer: Stephan Dühr, M. Außendorf, J. Steffens, P. Storz, M. v. Wieringen -- You received this message because you are subscribed to the Google Groups "bareos-users" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. For more options, visit https://groups.google.com/d/optout.
