Backup Failed with Errors

Hi,

Got this error messages: Please guide what to do?

14th Apr 2014 1.48.42 PM  Error The activity failed: A filesystem operation failed. 14th Apr 2014 1.48.42 PM  Error A filesystem operation failed while processing 'Database/OBFW_Database.sql' for backup.
If the following error message is not clear as to the problem and the issue persists, please contact support providing the complete event log for the activity. Diagnostic information follows:

Failed at: 430(/home/deathear/public_html/blog/wp-content/plugins/wponlinebackup/include/tables.php)
Attempt to write to file /home/deathear/public_html/blog/wp-content/plugins/wponlinebackup/tmp/gzipbuffer.af6af23b9526df4dd60c7daa61400123231c0992.php only partially succeeded. Only 16337 of 40960 bytes were written. (3424256 bytes already written.) PHP last error: An error happened at: file.php(82)
opendir(/home/deathear/public_html/blog/wp-content/cache/db/000000/options_comments/): failed to open dir: No such file or directory 14th Apr 2014 1.48.34 PM  Information Initialisation completed. 14th Apr 2014 1.48.34 PM  Information Ignoring comments that are marked as spam. 14th Apr 2014 1.48.34 PM  Information Ignoring comments in the trash. 14th Apr 2014 1.48.34 PM  Error Failed to retrieve field list from table 'wp_commentmeta': WPDB error: Table './deathear_8256274/wp_commentmeta' is marked as crashed and should be repaired. Last query: DESCRIBE <code>wp_commentmeta</code>. Table will be skipped. 14th Apr 2014 1.48.34 PM  Warning Table 'wp_commentmeta' has no PRIMARY or UNIQUE key! Backup of this table may be inconsistent; some rows could get missed. See FAQ for more information. 14th Apr 2014 1.48.34 PM  Error Failed to retrieve the index list from table 'wp_commentmeta': WPDB error: Table './deathear_8256274/wp_commentmeta' is marked as crashed and should be repaired. Last query: SHOW INDEXES FROM <code>wp_commentmeta</code>. 14th Apr 2014 1.48.34 PM  Warning Table 'jos_stats_agents' has no PRIMARY or UNIQUE key! Backup of this table may be inconsistent; some rows could get missed. See FAQ for more information. 14th Apr 2014 1.48.34 PM  Warning Table 'jos_rokversions' has no PRIMARY or UNIQUE key! Backup of this table may be inconsistent; some rows could get missed. See FAQ for more information. 14th Apr 2014 1.48.34 PM  Warning Table 'jos_osemsc_userinfo_view' has no PRIMARY or UNIQUE key! Backup of this table may be inconsistent; some rows could get missed. See FAQ for more information. 14th Apr 2014 1.48.34 PM  Warning Table 'jos_osemsc_member_view' has no PRIMARY or UNIQUE key! Backup of this table may be inconsistent; some rows could get missed. See FAQ for more information. 14th Apr 2014 1.48.34 PM  Warning Table 'jos_kunena_config_backup' has no PRIMARY or UNIQUE key! Backup of this table may be inconsistent; some rows could get missed. See FAQ for more information. 14th Apr 2014 1.48.34 PM  Warning Table 'jos_dms_order_item' has no PRIMARY or UNIQUE key! Backup of this table may be inconsistent; some rows could get missed. See FAQ for more information. 14th Apr 2014 1.48.34 PM  Warning Table 'jos_core_log_searches' has no PRIMARY or UNIQUE key! Backup of this table may be inconsistent; some rows could get missed. See FAQ for more information. 14th Apr 2014 1.48.34 PM  Warning Table 'jos_core_log_items' has no PRIMARY or UNIQUE key! Backup of this table may be inconsistent; some rows could get missed. See FAQ for more information. 14th Apr 2014 1.48.34 PM  Warning Table 'jos_bannertrack' has no PRIMARY or UNIQUE key! Backup of this table may be inconsistent; some rows could get missed. See FAQ for more information. 14th Apr 2014 1.48.34 PM  Information Backup starting... - See more at: https://www.oktodie.com/blog/wp-admin/admin.php?page=wponlinebackup&section=events&activity=1#sthash.Qv98XuAk.dpuf

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Online Backup for WordPress Plugin Version 3.0.4
WordPress Version: 3.5.1 (standalone)
PHP Version: 5.3.23
Server Software: Apache
MySQL Server Version: 5.1.68-cll-lve
MySQL Client Version: 1.0; MySQL Packet Size: 1?MiB
Memory: 256M; Post: 8M; Upload: 32M; Timeout: 600
Memory Changable: Yes; Admin Cache Size: 1.01?MiB
Status: 1 row, 14.85?KiB packet size, 997.41?KiB cache freed, 34.66?MiB memory used
Capabilities: hashcopy gzdeflate php5hash DES AES128 AES192 AES256
End of Information

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