postgres_metrics package

Submodules

postgres_metrics.apps module

class postgres_metrics.apps.PostgresMetrics(app_name, app_module)

Bases: django.apps.config.AppConfig

name = 'postgres_metrics'

verbose_name

postgres_metrics.metrics module

class postgres_metrics.metrics.AvailableExtensions

Bases: postgres_metrics.metrics.Metric

PostgreSQL can be extended by installing extensions with the CREATE EXTENSION command. The list of available extensions on each database is shown below.

label = 'Available Extensions'

slug = 'available-extensions'

sql = '\n SELECT\n name,\n default_version,\n installed_version,\n comment\n FROM\n pg_available_extensions\n ORDER BY\n name\n ;\n '

class postgres_metrics.metrics.CacheHitsMetric

Bases: postgres_metrics.metrics.Metric

The typical rule for most applications is that only a fraction of its data is regularly accessed. As with many other things data can tend to follow the 80/20 rule with 20% of your data accounting for 80% of the reads and often times its higher than this. Postgres itself actually tracks access patterns of your data and will on its own keep frequently accessed data in cache. Generally you want your database to have a cache hit rate of about 99%.

(Source: http://www.craigkerstiens.com/2012/10/01/understanding-postgres-performance/)

label = 'Cache Hits'

slug = 'cache-hits'

sql = "\n WITH cache AS (\n SELECT\n sum(heap_blks_read) heap_read,\n sum(heap_blks_hit) heap_hit,\n sum(heap_blks_hit) + sum(heap_blks_read) heap_sum\n FROM\n pg_statio_user_tables\n ) SELECT\n heap_read,\n heap_hit,\n CASE\n WHEN heap_sum = 0 THEN 'N/A'\n ELSE (heap_hit / heap_sum)::text\n END ratio\n FROM\n cache\n ;\n "

class postgres_metrics.metrics.IndexUsageMetric

Bases: postgres_metrics.metrics.Metric

While there is no perfect answer, if you’re not somewhere around 99% on any table over 10,000 rows you may want to consider adding an index. When examining where to add an index you should look at what kind of queries you’re running. Generally you’ll want to add indexes where you’re looking up by some other id or on values that you’re commonly filtering on such as created_at fields.

(Source: http://www.craigkerstiens.com/2012/10/01/understanding-postgres-performance/)

label = 'Index Usage'

slug = 'index-usage'

sql = '\n SELECT\n relname,\n 100 * idx_scan / (seq_scan + idx_scan) percent_of_times_index_used,\n n_live_tup rows_in_table\n FROM\n pg_stat_user_tables\n WHERE\n seq_scan + idx_scan > 0\n ORDER BY\n percent_of_times_index_used DESC\n ;\n '

class postgres_metrics.metrics.Metric

Bases: object

description

label = ''

slug = ''

sql = ''

class postgres_metrics.metrics.MetricRegistry

Bases: object

register(metric)

sorted

postgres_metrics.urls module

postgres_metrics.urls.re_path(route, view, kwargs=None, name=None, *, Pattern=<class 'django.urls.resolvers.RegexPattern'>)

postgres_metrics.views module

class postgres_metrics.views.MetricResult(connection, name)

Bases: object

alias

dsn

postgres_metrics.views.metrics_view(request, name)

Module contents