Linux - Comandi vari per gestire directory

Verificare dove è montata una directory

df nome_dir -h

Verificare quanto occupa una directory

totale occupato:   du -sh nome_dir

totale occupato dalle sottodirectory: du -h --max-depth=1

Linux -bash: fork: Resource temporarily unavailable

Se dovesse capitare che su Linux ad ogni comando che si cerca di eseguire si presenti l'errore

-bash: fork: Resource temporarily unavailable

Provare a stoppare tutti i processi con il comando

kill -9 -1

E poi restartare uno a uno tutti i processi della macchina.



Possibili operazioni sistemistiche per effettuare diagnosi (sostituire PID con il pid del processo)

Verificare i file aperti da un processo:

lsof -p PID | wc -l

Scrivere l'elenco dei file aperti su file

lsof -p PID > output.log

Vedere i thread aperti

ps -mo THREAD -p PID | awk '{print $5 }' | sort | uniq -c

SpagoBI - Gestione valori default JasperReport

The problem is that when you do not valorize an analytica driver Spagobi Server send to the engine an empty string as value.
The empty string is valid parameter value for jasper so it do not use the default one as expected. This managment of not valorized parameters can be improved in order to avoid this kind of problems. However for the moment I can suggets to you this workaround. In the jasper template for each parameter AAA that can be optionally valorized by the user define also another twin parameter named SAFE_AAA defined like this ...

($P{AAA} != null && $P{AAA}.trim().length() > 0) ? $P{AAA}: "my default value"

then use SAFE_AAA in place of AAA. Let me know if this work around works in your case. 

Java - Problematic frame - C [libc.so.6+0x72f33] __libc_calloc+0x93

# An unexpected error has been detected by Java Runtime Environment:
#
#  SIGSEGV (0xb) at pc=0x00002aaaab262f33, pid=5234, tid=1086544192
#
# Java VM: Java HotSpot(TM) 64-Bit Server VM (10.0-b19 mixed mode linux-amd64)
# Problematic frame:
# C  [libc.so.6+0x72f33]  __libc_calloc+0x93
#
# An error report file with more information is saved as:
# /mnt/bi/bisw/talend/KeyWord_2/Stg_Keyword_0.1/Stg_Keyword/hs_err_pid5234.log
#
# If you would like to submit a bug report, please visit:
#   http://java.sun.com/webapps/bugreport/crash.jsp



Soluzione: aggiungere questi parametri quando viene lanciato java

-Xms2048M -Xmx2048M -Dfile.encoding=UTF-8
-XX:+UseParallelGC
-XX:NewSize=512M
-XX:MaxNewSize=512M

MySql - Occupazione spazio nelle tabelle

SELECT
   table_schema,table_name, count(*) TABLES,
   round(sum(table_rows)/1000000,2) rows,
   round(sum(data_length)/(1024*1024*1024),2) DATA,
   round(sum(index_length)/(1024*1024*1024),2) idx, 
   round(sum(data_length+index_length)/(1024*1024*1024),2) total_size,
   round(sum(index_length)/sum(data_length),2) idxfrac
FROM
   information_schema.TABLES
group by table_schema,table_name
order by 7 desc

MySql - Salvataggio di tabella su file

Salvataggio di tabella su file:

SELECT * FROM prova
INTO OUTFILE '/mnt/prova.csv'
FIELDS TERMINATED BY ';' ENCLOSED BY '"' ESCAPED BY '\\' LINES TERMINATED BY '\n';

Se Infobright potrebbe dare il seguente errore:
The query includes syntax that is not supported by the Infobright Optimizer. Either restructure the query with supported syntax, or enable the MySQL Query Path in the brighthouse.ini file to execute the query with reduced performance. 

Per risolverlo eseguire prima lo statement:

set @bh_dataformat = 'txt_variable';

Caricamento da file:

LOAD DATA INFILE '/mnt/prova.csv' INTO TABLE prova1

Vertica - Query di monitoraggio

Verificare lo spazio occupato dalla tabelle sul disco

SELECT t.table_schema,t.table_name AS table_name,
SUM(ps.wos_row_count + ps.ros_row_count) AS row_count,
SUM(ps.wos_used_bytes + ps.ros_used_bytes)/(1024*1024) AS MB_count
FROM tables t
JOIN projections p ON t.table_id = p.anchor_table_id
JOIN projection_storage ps on p.projection_name = ps.projection_name
WHERE (ps.wos_used_bytes + ps.ros_used_bytes) > 500000
GROUP BY t.table_schema,t.table_name
ORDER BY MB_count DESC;

Vedere l'elenco della tabelle

SELECT * FROM tables;

Verificare le query attive

select node_name, user_name, client_hostname, session_id, transaction_start, statement_start, current_statement
from sessions

Killare una sessione
Inserire come parametro il campo session_id

SELECT CLOSE_SESSION('vertica01.pgh.wpahs774:0x1db5bb');