top: documented those newly added IO accounting fields

Signed-off-by: Jim Warner <james.warner@comcast.net>
This commit is contained in:
Jim Warner 2021-06-20 00:00:00 -05:00 committed by Craig Small
parent ae8d63addb
commit 24e4e1f5c3

View File

@ -64,7 +64,7 @@ memory statistics and data for other users requires root privileges
.
.\" Document /////////////////////////////////////////////////////////////
.\" ----------------------------------------------------------------------
.TH TOP 1 "April 2021" "procps-ng" "User Commands"
.TH TOP 1 "June 2021" "procps-ng" "User Commands"
.\" ----------------------------------------------------------------------
.nh
@ -1036,7 +1036,25 @@ is currently sleeping.
Running tasks will display a dash (`\-') in this column.
.TP 4
55.\fB nDRT \*(Em Dirty Pages Count \fR
55.\fB ioR \*(Em I/O Bytes Read \fR
The number of bytes a process caused to be fetched from the storage layer.
.TP 4
56.\fB ioRop \*(Em I/O Read Operations \fR
The number of read I/O operations (syscalls) for a process.
Such calls might not result in actual physical disk I/O.
.TP 4
57.\fB ioW \*(Em I/O Bytes Written \fR
The number of bytes a process caused to be sent to the storage layer.
.TP 4
58.\fB ioWop \*(Em I/O Write Operations \fR
The number of write I/O operations (syscalls) for a process.
Such calls might not result in actual physical disk I/O.
.TP 4
59.\fB nDRT \*(Em Dirty Pages Count \fR
The number of pages that have been modified since they were last
written to \*(AS.
Dirty pages must be written to \*(AS before the corresponding physical
@ -1045,7 +1063,7 @@ memory location can be used for some other virtual page.
This field was deprecated with linux 2.6 and is always zero.
.TP 4
56.\fB nMaj \*(Em Major Page Fault Count \fR
60.\fB nMaj \*(Em Major Page Fault Count \fR
The number of\fB major\fR page faults that have occurred for a task.
A page fault occurs when a process attempts to read from or write to a
virtual page that is not currently present in its address space.
@ -1053,7 +1071,7 @@ A major page fault is when \*(AS access is involved in making that
page available.
.TP 4
57.\fB nMin \*(Em Minor Page Fault count \fR
61.\fB nMin \*(Em Minor Page Fault count \fR
The number of\fB minor\fR page faults that have occurred for a task.
A page fault occurs when a process attempts to read from or write to a
virtual page that is not currently present in its address space.
@ -1061,50 +1079,50 @@ A minor page fault does not involve \*(AS access in making that
page available.
.TP 4
58.\fB nTH \*(Em Number of Threads \fR
62.\fB nTH \*(Em Number of Threads \fR
The number of threads associated with a process.
.TP 4
59.\fB nsIPC \*(Em IPC namespace \fR
63.\fB nsIPC \*(Em IPC namespace \fR
The Inode of the namespace used to isolate interprocess communication (IPC)
resources such as System V IPC objects and POSIX message queues.
.TP 4
60.\fB nsMNT \*(Em MNT namespace \fR
64.\fB nsMNT \*(Em MNT namespace \fR
The Inode of the namespace used to isolate filesystem mount points thus
offering different views of the filesystem hierarchy.
.TP 4
61.\fB nsNET \*(Em NET namespace \fR
65.\fB nsNET \*(Em NET namespace \fR
The Inode of the namespace used to isolate resources such as network devices,
IP addresses, IP routing, port numbers, etc.
.TP 4
62.\fB nsPID \*(Em PID namespace \fR
66.\fB nsPID \*(Em PID namespace \fR
The Inode of the namespace used to isolate process ID numbers
meaning they need not remain unique.
Thus, each such namespace could have its own `init/systemd' (PID #1) to
manage various initialization tasks and reap orphaned child processes.
.TP 4
63.\fB nsUSER \*(Em USER namespace \fR
67.\fB nsUSER \*(Em USER namespace \fR
The Inode of the namespace used to isolate the user and group ID numbers.
Thus, a process could have a normal unprivileged user ID outside a user
namespace while having a user ID of 0, with full root privileges, inside
that namespace.
.TP 4
64.\fB nsUTS \*(Em UTS namespace \fR
68.\fB nsUTS \*(Em UTS namespace \fR
The Inode of the namespace used to isolate hostname and NIS domain name.
UTS simply means "UNIX Time-sharing System".
.TP 4
65.\fB vMj \*(Em Major Page Fault Count Delta\fR
69.\fB vMj \*(Em Major Page Fault Count Delta\fR
The number of\fB major\fR page faults that have occurred since the
last update (see nMaj).
.TP 4
66.\fB vMn \*(Em Minor Page Fault Count Delta\fR
70.\fB vMn \*(Em Minor Page Fault Count Delta\fR
The number of\fB minor\fR page faults that have occurred since the
last update (see nMin).