go.chromium.org/luci@v0.0.0-20240309015107-7cdc2e660f33/logdog/server/cmd/logdog_archivist/flags.go (about)

     1  // Copyright 2021 The LUCI Authors.
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //      http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  
    15  package main
    16  
    17  import (
    18  	"flag"
    19  	"time"
    20  
    21  	"go.chromium.org/luci/common/errors"
    22  )
    23  
    24  // CommandLineFlags contains archivist service configuration.
    25  //
    26  // It is exposed via CLI flags.
    27  type CommandLineFlags struct {
    28  	// StagingBucket is the name of the Google Storage bucket to use for staging
    29  	// logs.
    30  	//
    31  	// Required.
    32  	StagingBucket string
    33  
    34  	// MaxConcurrentTasks is the maximum number of archival tasks to process
    35  	// concurrently or 0 for unlimited.
    36  	//
    37  	// Default is 1.
    38  	MaxConcurrentTasks int
    39  
    40  	// LeaseBatchSize is the number of archival tasks to lease from the taskqueue
    41  	// per one cycle.
    42  	//
    43  	// TaskQueue has a limit of 10qps for leasing tasks, so the batch size must
    44  	// be set to:
    45  	// LeaseBatchSize * 10 > (max expected stream creation QPS)
    46  	//
    47  	// In 2020, max stream QPS is approximately 1000 QPS.
    48  	//
    49  	// Default is 500.
    50  	LeaseBatchSize int
    51  
    52  	// LeaseTime is the amount of time to to lease the batch of tasks for.
    53  	//
    54  	// We need:
    55  	// (time to process avg stream) * LeaseBatchSize < LeaseTime
    56  	//
    57  	// As of 2020, 90th percentile process time per stream is ~5s, 95th
    58  	// percentile of the loop time is 25m.
    59  	//
    60  	//
    61  	// Default is 40 min.
    62  	LeaseTime time.Duration
    63  
    64  	// Entries below specify defaults for archive indexes generation. Individual
    65  	// projects may override these default values in their project configs.
    66  
    67  	// ArchiveIndexStreamRange, if not zero, is the maximum number of stream
    68  	// indexes between index entries.
    69  	//
    70  	// Default is 0.
    71  	ArchiveIndexStreamRange int
    72  
    73  	// ArchiveIndexPrefixRange, if not zero, is the maximum number of prefix
    74  	// indexes between index entries.
    75  	//
    76  	// Default is 0.
    77  	ArchiveIndexPrefixRange int
    78  
    79  	// ArchiveIndexByteRange, if not zero, is the maximum number of log data bytes
    80  	// between index entries.
    81  	//
    82  	// Default is 0.
    83  	ArchiveIndexByteRange int
    84  
    85  	// CloudLoggingExportBufferLimit, is the maximum number of megabytes that
    86  	// the CloudLogger will keep in memory per concurrent-task before flushing
    87  	// them out.
    88  	//
    89  	// Default is 10.
    90  	// Must be > 0.
    91  	CloudLoggingExportBufferLimit int
    92  }
    93  
    94  // DefaultCommandLineFlags returns CommandLineFlags with populated defaults.
    95  func DefaultCommandLineFlags() CommandLineFlags {
    96  	return CommandLineFlags{
    97  		MaxConcurrentTasks:            1,
    98  		LeaseBatchSize:                500,
    99  		LeaseTime:                     40 * time.Minute,
   100  		CloudLoggingExportBufferLimit: 10,
   101  	}
   102  }
   103  
   104  // Register registers flags in the flag set.
   105  func (f *CommandLineFlags) Register(fs *flag.FlagSet) {
   106  	fs.StringVar(&f.StagingBucket, "staging-bucket", f.StagingBucket,
   107  		"GCE bucket name to use for staging logs.")
   108  	fs.IntVar(&f.MaxConcurrentTasks, "max-concurrent-tasks", f.MaxConcurrentTasks,
   109  		"Maximum number of archival tasks to process concurrently or 0 for unlimited.")
   110  	fs.IntVar(&f.LeaseBatchSize, "lease-batch-size", f.LeaseBatchSize,
   111  		"How many tasks to lease per cycle.")
   112  	fs.DurationVar(&f.LeaseTime, "lease-time", f.LeaseTime,
   113  		"For how long to lease archival tasks.")
   114  	fs.IntVar(&f.ArchiveIndexStreamRange, "archive-index-stream-range", f.ArchiveIndexStreamRange,
   115  		"The maximum number of stream indexes between index entries.")
   116  	fs.IntVar(&f.ArchiveIndexPrefixRange, "archive-index-prefix-range", f.ArchiveIndexPrefixRange,
   117  		"The maximum number of prefix indexes between index entries.")
   118  	fs.IntVar(&f.ArchiveIndexByteRange, "archive-index-byte-range", f.ArchiveIndexByteRange,
   119  		"The maximum number of log data bytes between index entries.")
   120  	fs.IntVar(&f.CloudLoggingExportBufferLimit, "cloud-logging-export-buffer-limit", f.CloudLoggingExportBufferLimit,
   121  		"Maximum number of bytes that the Cloud Logger will keep in memory before flushing out.")
   122  }
   123  
   124  // Validate returns an error if some parsed flags have invalid values.
   125  func (f *CommandLineFlags) Validate() error {
   126  	if f.StagingBucket == "" {
   127  		return errors.New("-staging-bucket is required")
   128  	}
   129  	if f.CloudLoggingExportBufferLimit == 0 {
   130  		return errors.New("-cloud-logging-export-buffer-limit must be > 0")
   131  	}
   132  	return nil
   133  }