MEMINFO(1) General Commands Manual MEMINFO(1)

meminfo — display physical memory usage breakdown

meminfo [--summary] [--zones] [--raw] [--all] [--quiet] [--csv path] [--perfdata path] [--interval seconds] [--count n] [--duration seconds]

meminfo displays a breakdown of physical memory usage by category. By default each category is printed as its own section: a header line with the category's page count and size, followed by indented subcategory rows whose percentage bars are relative to that category's total. Any portion of a category not covered by its subcategories is shown as an Unaccounted row. A final Physical Memory summary breaks the total down into the main categories, and a Swap section follows.

The following options are available:

Show only the Physical Memory summary and the Swap section, omitting the per-category detail sections.
Expand the aggregate wired Zones row into one row per kernel zone. This requires root privileges; without them, meminfo prints a warning and shows the aggregate Zones total instead.
Show raw metric names (e.g. anonymous_purgeable) instead of human-readable display names (e.g. Purgeable).
Show all metrics, including those that are normally hidden when their value is zero (e.g. Secluded) or below 1 MB (wired sites), and overlapping subtotals that are normally excluded from the breakdown (e.g. Purgeable, Shared cache). MTE-related metrics are also included regardless of hardware capability.
Suppress summary output to stdout. Useful when only CSV or perfdata output is desired.
path
Write CSV output to path. The first line is a header row; subsequent lines are data rows. All memory values are in bytes. Without --interval, a single data row is written.
seconds
Sample repeatedly, sleeping seconds between samples. Fractional values are accepted (e.g. 0.5).

In the default formatted mode, the screen is cleared before each sample. In CSV mode, each sample is emitted as an additional data row after a single header.

n
Stop after n samples. Requires --interval to have any effect; without it, only one sample is taken regardless.
seconds
Stop after seconds have elapsed. Requires --interval to have any effect.
path
Write output to a perfdata file at path. Each memory category is recorded as a separate metric in bytes. Individual wired sites (category=wired) and carveout regions (category=static_carveouts) are included as additional metrics. When combined with --interval, each sample is written as a separate group in the same perfdata file.

When --interval is active, meminfo installs signal handlers for SIGINT and SIGTERM. Both --count and --duration may be specified together; sampling stops when either limit is reached.

The following categories are displayed in the formatted output. Together they make up the Physical Memory summary.

Anonymous
Pageable memory allocated by applications that are not backed by a file.

Active
The subset of anonymous pages on the active queue.
Inactive
The subset of anonymous pages on the inactive queue.
Purgeable
The subset of anonymous pages that the system may reclaim without preserving contents (i.e. VM_PURGABLE_VOLATILE).
Cached files
Pageable memory backed by files on disk (e.g. mapped files, shared libraries, caches).

Active
The subset of file-backed pages on the active queue.
Inactive
The subset of file-backed pages on the inactive queue.
Speculative
Pages read speculatively from disk that have not yet been referenced.
Secluded
File-backed pages that are secluded. Only shown when non-zero.
Shared cache
Pages used by the shared cache (dyld shared region).
Executable
Pages containing executable code from mapped binaries.
Compressor
Memory consumed by the in-memory compressor to store compressed data and, on MTE-capable systems, compressed tags.

Compressed data
The subset of compressor pages holding compressed page data (excluding tag storage).
Compressed tags
The bytes consumed by compressed tag storage in the compressor. Only shown on MTE-capable systems.
Free
Memory not currently in use.

Tag storage
Tag storage pages that are not currently in use. Only shown on MTE-capable systems.
Wired
Memory that cannot be paged out or compressed (kernel data structures, IOSurfaces, etc.). Individual kernel allocation sites are listed as indented subcategories. Gathering them requires root privileges or the com.apple.private.memoryinfo entitlement; without them only the category total is shown.
Static carveouts
Memory reserved at boot time by the kernel. Individual carveout regions from the device tree are listed as indented subcategories. Nested or overlapping regions are clipped so each physical page is counted once, and any unnamed remainder is aggregated into an row.

The Swap category is displayed below the Physical Memory summary and is not part of the physical memory total.

Swap
Compressor pages currently stored in the on-disk swapfile.

Swapped data
The subset of swap pages holding compressed page data.

Each category is printed as a section headed by its page count and size. Indented subcategory rows show a label, page count, size in megabytes, a fixed-width visual bar, and a percentage relative to the enclosing category; they are sorted largest first, and any remainder appears as an Unaccounted row. A trailing Physical Memory section breaks the total down into the main categories, with bars and percentages relative to physical memory.

A header row followed by one data row per sample. The first two columns are datetime (ISO 8601) and abstime (Unix epoch with millisecond precision). All memory values are in bytes.

A perfdata file containing one metric per memory category. With --interval, each sample is written as a separate group. All values are in bytes.

The meminfo utility exits 0 on success, and >0 if an error occurs.

Display a one-shot breakdown (wired sites require root):

# meminfo

Show only the physical-memory summary and swap:

$ meminfo --summary

Expand wired zones into individual rows:

# meminfo --zones

Show everything, including hidden and overlapping subtotals:

# meminfo --all

Sample every 2 seconds, stop after 10 samples, output as CSV:

$ meminfo --csv /tmp/mem.csv --interval 2 --count 10

Stream CSV for 60 seconds at half-second intervals:

$ meminfo --csv /tmp/mem.csv --interval 0.5 --duration 60

memory_pressure(1), top(1), vm_stat(1), zprint(1)

March 13, 2026 macOS 26