possible to find a paper titled as such with sections starting with
"Interpreting system activity".
There is a "Monitoring System Performance" section present from the 4.1BSD
Installing and Operating paper up to and including the 4.4BSD paper. The advice
in this section has not aged very well.
From "Installing and Operating 4.3BSD-tahoe UNIX on the VAX":
"Cumulatively on one of our large machines we average about 60-100
context switches and interrupts per second and about 70-120 system calls
per second"
bootpages is set to the pages allocated via uvm_pageboot_alloc().
poolpages is calculated from the list of pools nr_pages members.
this brings us closer to having a valid total of pages known by
the system, vs actual pages originally managed.
XXX: poolpages needs some handling for PR_RECURSIVE pools still.
in PR kern/52639, as well as some general cleaning-up...
(As proposed on tech-kern@ with additional changes and enhancements.)
Details of changes:
* All history arguments are now stored as uintmax_t values[1], both in
the kernel and in the structures used for exporting the history data
to userland via sysctl(9). This avoids problems on some architectures
where passing a 64-bit (or larger) value to printf(3) can cause it to
process the value as multiple arguments. (This can be particularly
problematic when printf()'s format string is not a literal, since in
that case the compiler cannot know how large each argument should be.)
* Update the data structures used for exporting kernel history data to
include a version number as well as the length of history arguments.
* All [2] existing users of kernhist(9) have had their format strings
updated. Each format specifier now includes an explicit length
modifier 'j' to refer to numeric values of the size of uintmax_t.
* All [2] existing users of kernhist(9) have had their format strings
updated to replace uses of "%p" with "%#jx", and the pointer
arguments are now cast to (uintptr_t) before being subsequently cast
to (uintmax_t). This is needed to avoid compiler warnings about
casting "pointer to integer of a different size."
* All [2] existing users of kernhist(9) have had instances of "%s" or
"%c" format strings replaced with numeric formats; several instances
of mis-match between format string and argument list have been fixed.
* vmstat(1) has been modified to handle the new size of arguments in the
history data as exported by sysctl(9).
* vmstat(1) now provides a warning message if the history requested with
the -u option does not exist (previously, this condition was silently
ignored, with only a single blank line being printed).
* vmstat(1) now checks the version and argument length included in the
data exported via sysctl(9) and exits if they do not match the values
with which vmstat was built.
* The kernhist(9) man-page has been updated to note the additional
requirements imposed on the format strings, along with several other
minor changes and enhancements.
[1] It would have been possible to use an explicit length (for example,
uint64_t) for the history arguments. But that would require another
"rototill" of all the users in the future when we add support for an
architecture that supports a larger size. Also, the printf(3) format
specifiers for explicitly-sized values, such as "%"PRIu64, are much
more verbose (and less aesthetically appealing, IMHO) than simply
using "%ju".
[2] I've tried very hard to find "all [the] existing users of kernhist(9)"
but it is possible that I've missed some of them. I would be glad to
update any stragglers that anyone identifies.
Disk statistics are collected in a fixed size array, that got corrupted
when a disk was detached. Adapt by skipping entries of detached disks
and detect reused disknames at the array end.
by the number of concurrent I/O requests. Also introduce a new disk_wait()
function to measure requests waiting in a bufq.
iostat -y now reports data about waiting and active requests.
So far only drivers using dksubr and dk, ccd, wd and xbd collect data about
waiting requests.
races while allowing consistent lockless sampling of the per-cpu
statistics without atomic operations. Update comment describing
the locking protocol to include this.
These files were fumble-fingered out of the last commit.
- vcache_get() retrieves a referenced and initialised vnode / fs node pair.
- vcache_remove() removes a vnode / fs node pair from the cache.
On cache miss vcache_get() calls new vfs operation vfs_loadvnode() to
initialise a vnode / fs node pair. This call is guaranteed exclusive,
no other thread will try to load this vnode / fs node pair.
Convert ufs/ext2fs, ufs/ffs and ufs/mfs to use this interface.
Remove now unused ufs/ufs_ihash
Discussed on tech-kern.
Welcome to 6.99.41