# =============================================================================
#  settings.conf - every tunable value for the NFS kit, in one place
# =============================================================================
#  Both start-nfs.sh and test-nfs.sh read this file.
#  After changing a value in sections 1-3, run ./start-nfs.sh again so the
#  NFS server and the test mount pick it up.
#
#  Any value can also be overridden for a single run from the command line:
#      DURATION=30 ./test-nfs.sh seqread
# =============================================================================


# -----------------------------------------------------------------------------
#  1. The test export (server side)
# -----------------------------------------------------------------------------
#  The kit uses RHEL's normal kernel NFS server (nfs-server.service); Linux
#  has only one. It ADDS one export, in its own file, and changes no other
#  export. The export is allowed ONLY for 127.0.0.1, so no other machine can
#  mount it and no firewall change is needed.
#  "./start-nfs.sh cleanup" removes everything the kit created.
EXPORT_DIR="${EXPORT_DIR:-/srv/nfs-perf-test}"       # folder that is shared (exported)
EXPORT_CLIENT="127.0.0.1"                            # the only client allowed to mount it

# Export options (man 5 exports). "sync" is the RHEL default and the safe
# choice: the server writes data to disk before it says "done".
# "async" is much faster for writes, but data can be lost if the server
# crashes (see PERFORMANCE-METRICS.md, section 7).
EXPORT_OPTIONS="${EXPORT_OPTIONS:-rw,sync,root_squash,no_subtree_check}"

TEST_EXPORTS_FILE="/etc/exports.d/nfs-perf-test.exports"    # our export line
TEST_NFS_CONF="/etc/nfs.conf.d/nfs-perf-test.conf"          # our server settings
TEST_STATE_FILE="/etc/nfs-perf-test.state"                  # remembers what to undo


# -----------------------------------------------------------------------------
#  2. NFS server settings
# -----------------------------------------------------------------------------
#  nfsd threads: how many client requests the server works on at the same
#  time. RHEL 9 default: 8. Busy servers with many clients use 32-128.
#  NOTE: this changes the thread count of the whole NFS server on this host
#  (written to /etc/nfs.conf.d/nfs-perf-test.conf; "cleanup" removes it).
NFSD_THREADS="${NFSD_THREADS:-8}"


# -----------------------------------------------------------------------------
#  3. The test mount (client side, on this same machine)
# -----------------------------------------------------------------------------
#  start-nfs.sh mounts the test export here, over the loopback interface.
#  All tests read and write through this mount, exactly like a real client.
MOUNT_POINT="${MOUNT_POINT:-/mnt/nfs-perf-test}"

NFS_VERSION="${NFS_VERSION:-4.2}"    # 4.2 (RHEL 9 default), 4.1, 4.0 or 3
RSIZE_KB="${RSIZE_KB:-1024}"         # largest READ  per request (1024 = RHEL default and maximum)
WSIZE_KB="${WSIZE_KB:-1024}"         # largest WRITE per request
NCONNECT="${NCONNECT:-1}"            # TCP connections per mount (1 = default, up to 16)


# -----------------------------------------------------------------------------
#  4. Test data (created on the export by test-nfs.sh)
# -----------------------------------------------------------------------------
#  data.0, data.1, ... : one file of DATA_FILE_MB per sequential stream.
#  The random-I/O tests all use data.0.
DATA_FILE_MB="${DATA_FILE_MB:-1024}"

# "yes" = empty the page cache before every read test (sync, then
# drop_caches), so reads come from DISK. "no" = reads come from the server's
# memory (the files were just written), which measures NFS itself.
# The cache is shared by every program on this machine; see section 4.3 of
# PERFORMANCE-METRICS.md before switching it on for a production server.
DROP_CACHES="${DROP_CACHES:-no}"


# -----------------------------------------------------------------------------
#  5. How hard and how long each test runs
# -----------------------------------------------------------------------------
DURATION="${DURATION:-10}"                  # seconds of load for each test run

# "seqwrite", "seqread": parallel streams, 1 MiB blocks, requests in flight per stream.
SEQ_STREAMS="${SEQ_STREAMS:-1}"
SEQ_QUEUE_DEPTH="${SEQ_QUEUE_DEPTH:-8}"

# "randread", "randwrite", "cpu": 4 KiB blocks at random places in data.0.
RANDOM_JOBS="${RANDOM_JOBS:-4}"             # parallel jobs (like 4 application threads)
RANDOM_QUEUE_DEPTH="${RANDOM_QUEUE_DEPTH:-16}"   # requests in flight per job

# "latency", "errors": a steady, realistic load of LOAD_RATE 4 KiB requests
# per second (70% reads, 30% writes), one at a time.
LOAD_RATE="${LOAD_RATE:-500}"

# "metadata": this many workers create (and afterwards delete) small files.
WORKERS="${WORKERS:-8}"
SMALL_FILE_KB="${SMALL_FILE_KB:-4}"

# "concurrency": clients reading at the same time, step by step. Each one
# waits for its answer before it sends the next request.
CONCURRENCY_LEVELS="${CONCURRENCY_LEVELS:-1 4 16 64 128}"

# "memory": files held open at the same time while memory is measured.
MEMORY_OPEN_FILES="${MEMORY_OPEN_FILES:-5000}"

STARTUP_ROUNDS="${STARTUP_ROUNDS:-3}"       # restarts measured by the "startup" test
RECOVERY_TIMEOUT="${RECOVERY_TIMEOUT:-300}" # seconds to wait for clients to work again

# The "startup" test restarts the NFS server. When the server also exports
# other folders (real clients may use them), the test is skipped unless
# this is "yes".
ALLOW_SERVER_RESTART="${ALLOW_SERVER_RESTART:-no}"


# -----------------------------------------------------------------------------
#  6. Pass / fail targets
# -----------------------------------------------------------------------------
#  Sensible starting points for a RHEL 9 file server with local SSD storage
#  and a 10 Gbit/s network. Adjust them to your own needs. A result that
#  misses its target is reported as FAIL; see PERFORMANCE-METRICS.md.
TARGET_STARTUP_MAX_MS="${TARGET_STARTUP_MAX_MS:-5000}"           # start until the server answers
TARGET_RECOVERY_MAX_S="${TARGET_RECOVERY_MAX_S:-100}"            # restart until clients can create files again
TARGET_SEQWRITE_MIN_MBPS="${TARGET_SEQWRITE_MIN_MBPS:-200}"      # MB/s, at least
TARGET_SEQREAD_MIN_MBPS="${TARGET_SEQREAD_MIN_MBPS:-500}"        # MB/s, at least
TARGET_RANDREAD_MIN_IOPS="${TARGET_RANDREAD_MIN_IOPS:-10000}"    # 4 KiB reads per second
TARGET_RANDWRITE_MIN_IOPS="${TARGET_RANDWRITE_MIN_IOPS:-1000}"   # 4 KiB writes per second
TARGET_LATENCY_P95_MAX_MS="${TARGET_LATENCY_P95_MAX_MS:-5}"      # 95% of requests faster than
TARGET_LATENCY_P99_MAX_MS="${TARGET_LATENCY_P99_MAX_MS:-10}"     # 99% of requests faster than
TARGET_ERRORS_MAX_PCT="${TARGET_ERRORS_MAX_PCT:-0}"              # failed requests, at most %
TARGET_METADATA_MIN_PER_S="${TARGET_METADATA_MIN_PER_S:-500}"    # small files created per second
TARGET_CONCURRENCY_MIN="${TARGET_CONCURRENCY_MIN:-64}"           # clients served with p99 <= target
TARGET_CPU_MAX_US_PER_OP="${TARGET_CPU_MAX_US_PER_OP:-50}"       # nfsd CPU microseconds per 4 KiB read
TARGET_MEMORY_MAX_KB_PER_FILE="${TARGET_MEMORY_MAX_KB_PER_FILE:-4}"  # server memory per open file