Mesh Info

mesh-info is an eager resident service that keeps a fresh resource snapshot for each visible host. It samples local CPU, memory, swap, work-directory disk space, and active/inactive paglet counts, then exchanges bounded snapshot batches with peer mesh-info services.

Snapshots also include host tags and properties advertised by paglets host --tag TAG --property KEY=VALUE, so placement and diagnostics can use the same host-role vocabulary.

The core contract is:

from paglets.system.mesh_info import MESH_INFO, GET_LANDSCAPE, SELECT_TARGETS

Useful CLI commands:

uv run paglets mesh summary
uv run paglets mesh targets --max-load-per-cpu 1.0 --disk 1G
uv run paglets mesh targets --json

The summary command prints the fresh landscape known to the entry host. The targets command applies placement constraints and ranks eligible hosts by load, CPU, memory pressure, and work-storage pressure. Both text tables include active and inactive paglet counts for each host. Use optional --entry HOSTNAME to choose a discovered entry host by name.

Programmatic target selection:

from paglets.core.runtime_values import ServiceScope
from paglets.system.mesh_info import MESH_INFO, SELECT_TARGETS, TargetSelectionRequest

mesh_info = self.require_contract(MESH_INFO, operation=SELECT_TARGETS, scope=ServiceScope.LOCAL)
targets = mesh_info.call(
    SELECT_TARGETS,
    TargetSelectionRequest(limit=4, max_load_per_cpu=1.0, min_work_free_bytes=1024**3),
)

mesh-info is intentionally a resident service rather than a one-shot clone collector: each host maintains its own current view, and schedulers can query the nearest local service repeatedly without fan-out for every placement decision.