Re: [Libguestfs] [PATCH nbdkit v4 08/15] log: Log extents requests.

Typical output: 2019-03-26 18:22:17.287434 connection=2 Extents id=2 offset=0x0 count=0x40000000 req_one=1 ... 2019-03-26 18:22:17.290040 connection=2 ...Extents id=2 extents=[{ offset=0x0, length=0x250000, type=0 }, { offset=0x250000, length=0x7db0000, type=3 }, { offset=0x8000000, length=0x8000, type=0 }, { offset=0x8008000, length=0x38000, type=3 }, { offset=0x8040000, length=0x208000, type=0 }, { offset=0x8248000, length=0x7db8000, type=3 }, { offset=0x10000000, length=0x208000, type=0 }, { offset=0x10208000, length=0x7df8000, type=3 }, { offset=0x18000000, length=0x8000, type=0 }, { offset=0x18008000, length=0x38000, type=3 }, { offset=0x18040000, length=0x208000, type=0 }, { offset=0x18248000, length=0x7db8000, type=3 }, { offset=0x20000000, length=0x208000, type=0 }, { offset=0x20208000, length=0x7df8000, type=3 }, { offset=0x28000000, length=0x8000, type=0 }, { offset=0x28008000, length=0x38000, type=3 }, { offset=0x28040000, length=0x208000, type=0 }, { offset=0x28248000, length=0x7db8000, type=3 }, { offset=0x30000000, length=0x208000, type=0 }, { offset=0x30208000, length=0x7df8000, type=3 }, { offset=0x38000000, length=0x8000, type=0 }, { offset=0x38008000, length=0x38000, type=3 }, { offset=0x38040000, length=0x208000, type=0 }, { offset=0x38248000, length=0x7da8000, type=3 }, { offset=0x3fff0000, length=0x10000, type=0 }] return=0 As you can see this is logging the complete information as generated by the underlying plugin, not what is returned to the client (which is rather hard for the log filter to discern). It's probably more useful for debugging like this.

+ else { + FILE *fp; + char *extents_str = NULL; + size_t i, n, len = 0; + + fp = open_memstream (&extents_str, &len);

This filter writes to the file specified by the C<logfile=FILE> parameter. All lines include a timestamp, a connection counter, then details about the command. The following actions are logged: Connect, Read, Write, Zero, Trim, Flush, and Disconnect. Except for Connect