fe_

Unfortunately i cant find a tool to read the CM

With the standard LTFS-tools i can only read the data for loads, data writen and data readed. I will try to find a way to read the whole CM.

So the qualitiy of the tapes (i tried two) could be the reason of the high capacity usage-and the low backup-rate of 40 MB/s? Sorry, what is tape CM?

Thanks c3! I thought this is a effect of shoeshining, because this wiki-entry: "Shoe-shining decreases the attainable data transfer rate, drive and tape life, and tape capacity." I have done some tests the last days.. I got ~80 MB/s for backup and 70 MB/s for restore data. The files were >20 GB. But then, when i tried to backup a dataset (whole set 1,15 TB, files ~7-8GB) which i already unsuccessfully tried often before to backup to a LTO5 tape (1,31 TB), i get again about ~40 MB/s and the data doesnt fit again on the tape. As next, i combined a part (587 GB) of this dataset to 5 archives (7z) to get larger files. When i backuped these archives i get 70 MB/s, but these 587 GB takes 772 GB on the tape. I checked some other tapes which i have already recorded in the past. There i have 1200-1300 GB data on LTO5 tapes, with different file sizes (2-25 GB). Any idea whats going wrong?

Thanks c3 for your reply! I only backup or restore large files with about 5-30 GB each and dont use compression. Sometime means that i only have get one times a high rate when i restored data from tape back to HD, i think it was about 80-90 MB/s. At the rest of about 15 times when i used the tape drive for backup (most) or restoring (few) data with LTFS, i had about only 45-50 MB/s. My tapedrive is from "tandberg". When i tested the perfomance with the testing-tool from tandberg, i get ~120 MB/s. I was also able to store only ~1,05 TB on a 1,31 TB LTO5 tape. I think this is a normal effect of shoeshining. Yesterday i setup my OS new, because the installation was some years old. I installed again Win7 SP1 and LTFS. Since yesterday i get 80 MB/s on some quick tests! The tandberg testing-tool still reach ~120MB/s. I will do some more test in the next days to confirm the gain. Im already happy with this rate and hope i will be able to store more data on a tape as before. However, do you have some ideas to improve the performance even more? 120 MB/s should be able, but i dont would need more than 100 MB/s (Gbit-LAN).

Hello, im operating a LTO6 tapedrive in a LSI 9207-8i HBA and using LTFS on a Win7 system. I have the problem that the tapedrive isnt reading or writing fast enough although i read or write the date from a local hd with ~160 MB/s read/write. The tapedrive should be able to write/read with 54–160 MB/s (Specifications) but i sometimes reach only 45-50 MB/s and have the shoeshining-effect. Could the firmware / BIOS of the HBA a reason for this problem? Here are my current versions: Controller Number : 0 Controller : SAS2308_2(D1) PCI Address : 00:02:00:00 SAS Address : 500605b-0-08af-6420 NVDATA Version (Default) : 11.00.00.05 NVDATA Version (Persistent) : 11.00.00.05 Firmware Product ID : 0x2214 (IT) Firmware Version : 17.00.01.00 NVDATA Vendor : LSI NVDATA Product ID : SAS9207-8i BIOS Version : 07.33.00.00 UEFI BSD Version : 07.24.01.00 FCODE Version : N/A Thanks in advance!