[ https://issues.apache.org/jira/browse/AVRO-3094?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
radai rosenblatt updated AVRO-3094: ----------------------------------- Description: starting with 1.9, avro SpecificData supports per-class MODEL$ definitions, and looks for them on specific classes: {code:java} public static <T> SpecificData getForClass(Class<T> c) { if (SpecificRecordBase.class.isAssignableFrom(c)) { final Field specificDataField; try { specificDataField = c.getDeclaredField("MODEL$"); specificDataField.setAccessible(true); return (SpecificData) specificDataField.get(null); } catch (NoSuchFieldException e) { // Return default instance return SpecificData.get(); <======= EXPENSIVE } catch (IllegalAccessException e) { throw new AvroRuntimeException(e); } } return SpecificData.get(); } {code} when this is run vs specific record classes generated by older avro, which do not have field MODEL$ this reslts in a serious performance degradation. we've measured the impact on user code to be x3 slower in one case. here's a flame graph: !model$.png! under java 7+ it should be completely possible to cache the existence (or lack thereof) of MODEL$ using [ClassValue|https://docs.oracle.com/javase/7/docs/api/java/lang/ClassValue.html] which would also speed this up when operating on classes generated by more modern avro since it would avoid reflection was: starting with 1.9, avro SpecificData supports per-class MODEL$ definitions, and looks for them on specific classes: {code:java} public static <T> SpecificData getForClass(Class<T> c) { if (SpecificRecordBase.class.isAssignableFrom(c)) { final Field specificDataField; try { specificDataField = c.getDeclaredField("MODEL$"); specificDataField.setAccessible(true); return (SpecificData) specificDataField.get(null); } catch (NoSuchFieldException e) { // Return default instance return SpecificData.get(); <======= EXPENSIVE } catch (IllegalAccessException e) { throw new AvroRuntimeException(e); } } return SpecificData.get(); } {code} when this is run vs specific record classes generated by older avro, which do not have field MODEL$ this reslts in a serious performance degradation. we've measured the impact on user code to be x3 slower in one case (see attached flame graph) under java 7+ it should be completely possible to cache the existence (or lack thereof) of MODEL$ using [ClassValue|https://docs.oracle.com/javase/7/docs/api/java/lang/ClassValue.html] which would also speed this up when operating on classes generated by more modern avro since it would avoid reflection > performance regression in SpecificData.getForClass() when run with code > generated by older avro > ----------------------------------------------------------------------------------------------- > > Key: AVRO-3094 > URL: https://issues.apache.org/jira/browse/AVRO-3094 > Project: Apache Avro > Issue Type: Bug > Components: java > Affects Versions: 1.9.2, 1.10.2 > Reporter: radai rosenblatt > Priority: Major > Attachments: model$.png > > > starting with 1.9, avro SpecificData supports per-class MODEL$ definitions, > and looks for them on specific classes: > {code:java} > public static <T> SpecificData getForClass(Class<T> c) { > if (SpecificRecordBase.class.isAssignableFrom(c)) { > final Field specificDataField; > try { > specificDataField = c.getDeclaredField("MODEL$"); > specificDataField.setAccessible(true); > return (SpecificData) specificDataField.get(null); > } catch (NoSuchFieldException e) { > // Return default instance > return SpecificData.get(); <======= EXPENSIVE > } catch (IllegalAccessException e) { > throw new AvroRuntimeException(e); > } > } > return SpecificData.get(); > } {code} > when this is run vs specific record classes generated by older avro, which do > not have field MODEL$ this reslts in a serious performance degradation. we've > measured the impact on user code to be x3 slower in one case. here's a flame > graph: > !model$.png! > under java 7+ it should be completely possible to cache the existence (or > lack thereof) of MODEL$ using > [ClassValue|https://docs.oracle.com/javase/7/docs/api/java/lang/ClassValue.html] > which would also speed this up when operating on classes generated by more > modern avro since it would avoid reflection -- This message was sent by Atlassian Jira (v8.3.4#803005)